One-legged bodyweight squats + whatever heavy things you have available (e.g. bottles of water) in a backpack should be difficult enough. If you care about "functional strength" then it's arguably superior than barbell squats. And one-handed pushups are good substitute for benchpress.

Or go and find a tree branch for pullups/muscleups/dips.

Or do some 100m max effort hill repeats

Or jump squats

Or buy a futon and try moving that heavy and bulky mattress up a flight of stairs, alone.

There are hundreds of ways to get great workouts that do not require an indoor gym.

Pull-ups/muscleuos/dips won't work your glutes.

100m max effort hill repeats aren't really anabolic the same way squats are.

Jump squats aren't the same as pulling weight.

Your futon doesn't weigh as much as what I'm squatting and I'm much more likely to injure myself hauling it's awkward shape up stairs

There are hundreds of ways to get a workout but people go to the gym for good reasons

Those are great ways to get hurt mostly. If you're doing one legged squats you're going to tire out stabilizers before your glutes get a good workout. One handed pushups similar issue.

Great if that's what you want but not a replacement for proper weighted squats.

I can rep 450lbs, but pistol squats still kick my ass.

It's all stabilizers likely. I doubt you're using stressing your glutes or main muscles before your stabilizers give out.

You can work on your form, by slowing down the squat, using whatever weights you do have on hand (a broom handle or "yoke" with 5 gallon buckets filled with water/sand), dumbbells, kettle bells or weighted vest. You can also work on your fast twitch muscles and explosivity by jumping from a squat. Doing squats with a weight in only one hand also improves your core technique. Now is a great time to work on your neuromuscular fitness which will improve your lifts tremendously.

If you work on your form for 4-5 months, you aren't working on your form you're just losing gains.

I'm not working out with buckets full of liquid or materials thats hard to clean up.

Dumbells, kettle bells, and weighted vests are all off topic on the reply given the person was talking about doing bodyweight exercises.

Jump squats are great but not the same thing as properly weighted squats.

Neuromuscular fitness all well and good, but how many months now? My nervous system is great, what I'm missing is load.

Yea the workouts obviously won't be similar because you're not going to simulate that weight properly without a squat rack, but there are plenty of workouts you can do that will have similar positive effects on your body mechanics.

The exceptions are sport specific exercises which require certain movements that may require certain equipment.