I guess it depends on what you mean by "better".
SAR is a niche within a niche. I can totally understand why Soylent is 1000x better than other options.
But most backpackers are doing it for fun. Reducing weight and space is great, but there are plenty of much more enjoyable meals that are only marginally heavier/bulkier.
At least for me, cooking a good meal before bed is my favorite part of the day. I'll happily carry an extra pound or so to make that happen.
TBF, a lot of purely recreational backpackers care less about the pleasures of life. The type doing 14 hour days and so on. But that's a small market, and all the folks I've met on trails who are doing that sort of thing tend to be pretty price sensitive. Young folks with few savings taking a few months off work don't have three months of Soylent money ;-)
thru-hiker here. I did it on $2k of credit cards, which is the least of anyone i met personally. a dehydrated meal with 350 calories costs $5 minimum, requires cooking (fuel cost/weight), and requires time/energy for your body to digest.
a soylent powder meal costs $2.
It does require you to go to the supermarket, quickly buy some ingredients, and mix them together.
Here is an example: You can just buy oats, skim milk powder, peanuts (a bit better if you buy them crushed, or crush them), raisens, and dehydrated fruit & berries. I also add almonds, walnuts, chocolate, coconut. It works out to b/w 25-50cents a meal if you buy at Costco, and is very healthy. You can add sugar if you want (I add a little, and a very small amount of salt).
You can also customize to your heart's desire. Replace milk powder with whey powder. Peanuts with almonds, flax for omega 3s, etc.
There you have it - The wisdom to outcompete soylent on price, nutrition, and taste, and all by a lot.
Not saying that's a bad option, just different.
The disadvantages to soylent are taste, chewing difficulty/calories, preparation, it stops up your digestive tract, and takes much longer to become usable energy.
Ah, now I know why it sounded good to me. As a Swiss we basically grow up with that stuff.
SAR = search and rescue
REI = major American outdoor retailer
As for price, I bought a 30-day supply of camp food for less than $100 on amazon.
If your goals include speed or (less) weight, those freeze dried options are really far from ideal. To get around the weight issue you mostly need to plan and package your food yourself, which takes some time. If you're getting called out to do SAR you either need to have it done in advance or go with another option.
I can't really speak to the exact sodium content, but it's more than reasonable for emergency rations or hiking or SAR. You're not eating this stuff every meal for the rest of your life, and if you are, you deserve what you get.
It also gives you a lot more control over portions, which can be an issue as well. There is no point packing more than you are going to eat.
I brought up the salt content not for health reasons, but taste. Many of the ones I've tried have been so salty I've had trouble finishing them even after a day of backpacking.
So sure, you can combine your nutrient goo powder into a single sack, and thereby save a tiny fraction of the weight of the food (and water) itself. But you're splitting hairs.
I picked a mountain house pouch-based product at random on amazon, and the packaging weight was .06oz on a gross of 5oz, or 1.2%. Which is, of course, nothing. I have heard exactly zero people, ever, complain about the weight of their dried food packaging. I've heard lots of people complain about camping food being boring and flavorless.
If you like Soylent, fine, but the claim that this stuff is the obvious best product for campers is silly.
If I'm carrying a stove, then I'm carrying fuel too. That weight and space adds up. Even if I'm carrying my MSR Windburner, it's still about the size of my first aid kit. My old MSR PocketRocket was smaller by itself, but required a mess kit or a pot of some kind for the hot water. I could go with a soda can alcohol stove, but then if I spill my fuel I'm a bit boned and they aren't always the most reliable or efficient setups to begin with.
Soylent is: remove Soylent package from pack, dump approx 10 oz into Nalgene, add water (cold, filtered from a stream if possible), shake, and continue.
Cooking while backpacking is fun ... sometimes. Once in a while it's nice to take the time to put together some backcountry gourmet stuff.
But for just having the equivalent of emergency rations in my pack, Soylent really is better than the other choices.
Oh, and anecdotally: digestion is a pretty big deal when you get far enough away from civilization. I've had some Mountain House meals do some pretty unhappy things in my gut, and there's only so much cleanup that small wad of "oh-no" TP I carry around can do. Soylent tends to digest really well and not cause post-digestive messes. Unless, of course, you happen to be one of those many people who were allergic to one of their recent formulations.
The instructions on all the Mountain House stuff that I have say "add hot water and wait N minutes".
(But I agree with the gist of the argument, that things like Soylent and Tsogo are better for this use case anyway.)
I can also state that the majority of people I know care so much about weight that they would never carry mountain house type food around.
If we both extend our friends to the general public, we have a clash. Or, maybe, there are different types of people in the world, some of whom think that Soylent is a great alternative for many of the situations they find themselves in.
If everyone you know is different, congratulations. Enjoy your nutrient goo.
I also participate (professionally) in uSAR via a technical rescue team for a decently large municipality. We don't take food on call outs and have no idea how long an extrication will take for example. When I am at work, I often don't eat for two, three, or four hours past "lunch time" or "dinner time" due to calls. Soylent is not an option anymore than drinking a protein shake on a call. Not happening.
Soylent is just very good at marketing to people unfamiliar with protein powder.
I though Soylent was good because it covers all your nutritional requirements (haven't tried it) - this trader joe's has the same nutritional content?
What I don't understand: the REI market is the one place where Soylent is inarguably better than any other product in its niche, and nobody seems to give a shit about that.
I carry a bag of dry Soylent in my SAR pack. When I get sent out on an assignment, I have no idea how long I might be out for. For less weight than any other option, I have dinner and breakfast and lunch if necessary.
If I know in advance I'm going to be out hiking for more than about three hours, a pre-mixed solution of it in a Nalgene, with a quick chug here and there, really beats back the fatigue.
The REI market is not small, and it's got a huge focus on ultralight, ultralight, ultralight now. Soylent really seems to be missing an opportunity here.