I know you disagree with how I'm keeping my cat, but that's ok. You should see her when I do open the door! I take her with me (in my arms) to get the mail some mornings, and she is really eager to nope out and get back inside. I have a shitty screen door in the front that doesn't even have a latch and she could easily just push it open with her nose and go outside. I have a shitty screen over my bedroom window too (the one she sits at to watch birds) that has holes in it that she could easily fit through, and yet she doesn't jump out the window (first floor, it's like 3 feet off the ground, if even). My cat homegirl is peeeeerrrrfectly happy to just hang out and sleep in sun spots on the carpet all day long. The two times she got out were because she was spooked by something inside (I dropped a metal pot on the tile one time, and the other time, my SO turned on the stereo and the volume was waaaay up really loud), and she just jammed into the flimsy screen door and hid under the bush right outside.
Other than that, she's never tried to get out, even though she knows she can just push open the screen door, literally whenever she wants to, she chooses not to.
Also, jumping back a bit, remember the shitty window screen I have? It is shredded and has big holes because the feral strays and other random neighborhood cats have seen my cat sitting there, and they've climbed up the screen multiple times, shredding the shit at it to try to get at her. My cat is spayed, but the others are not, and even my neighbor doesn't vaccinate her own indoor/outdoor cats. It's bullshit that I have to even supervise my cat's time at that one particular window (fortunately there are others that neighborhood cats don't bother her at) because of the extremely aggressive and unvaccinated cats that live directly around my house.
Plus, I don't work outside the home, so I am here aaaaaaaallllllll day to give my kitty LOTS of attention. She wants for nothing. For reals.