If I ever park and wonder “damn did I lock my car” I can look at my key fob and see if it has a locked or unlocked padlock on it. As long as I remember sometime within like 20 minutes of parking (assuming I spend 20 minutes walking away from it in a straight line), I can lock it if I _did_ forget. I’ll get confirmation that it locked if I do that and the command makes it through.
Mine also works even where there’s no cell reception!
Which is all to say… I’d prefer better key fobs instead of cellular modems and cloud services.
I see several aftermarket systems here: https://www.popularmechanics.com/cars/a34512303/best-remote-...
I doubt it would ever solve my problem (they're still not going to offer half the functionality on a M/T vehicle), but there's no reason they couldn't offer something like this as a couple hundred dollar option on most of their vehicles. They already basically have all the hardware in the car I figure.
I've had to fetch something from my car while my gf had the car keys with her, I could just open it with my phone. It's useful.