I haven't worked in game dev in decades, but I remember that just network synchronization could be tricky because the degree to which a door is open could lead to very different outcomes in a game. Eg take a shooter game:
Does the door block/deflect bullets?
Yes? Well now you need to make sure to synchronize clients really cleverly because each player will see a different state of the door depending on their latency. Whether they can shoot through the opening is relative to each clients' reference frame.
Oh, just make the server decide you say? Well, now all your inputs have a perceptible delay because your client has to wait for confirmation from the server, or you'll often see jarring prediction error correction when the thing you predicted is wrong.
A huge amount of research and work has gone into this and yet there's still no silver bullet.
That you think this is all solved just says that you know very little of the problem area - which is ok - but then you should not be making broad and confident statements about it. A touch of humility doesn't hurt.
Everything in games can be complicated: physics, doors, AI, network. Even the first line of that video description.
I think that just proves my original point: it's clickbait to single out doors as being exceptionally hard versus everything else in game design.
That's a fair point, but I think the charitable reading of the title is that amongst all the complicated things, a conceptually simple object like a door can still be very deceptively complex.
I sometimes get an urge to work on the myriad of game ideas I've written down over the years. And every time I remind myself that what I really like is the "idea" of making a game, not the actual process. Because the actual process is a draining, thankless and often rage inducing process. The actual building of a game is 95% of the time spent on stupid little details like making a door work properly.
And it is for that reason that I really admire game developers, particularly indie ones. It takes an insane amount of willpower, mental fortitude and wits to take a game from idea to playable product. And you then have to contend with one of the most toxic and volatile consumer groups in existence.
Yeah, I agree. I actually started out learning programming as a pre-teen by making my own games. It can be a lot of fun at times, but a lot of frustration too, and I can see how the latter eclipses the former as as you scale into a more complex game and with a bigger team.
It's not an easy job that's for sure.
Never mind a door simulated at the level of "I am opening it just wide enough for me to get outside with some food and water for the semi-feral cats who live under my house, with minimum opportunity for them to run inside before they're distracted with that food, also I have to kick it to get it open now because this is New Orleans and the house just settled a little more after Ida and now the frame's a little less square". Which is an interaction I have with a door every morning without ever thinking about the door.
There's also a quote from a lead developer at an AAA team saying that doors are the hardest thing to get right. Everything in a video game is a thin veneer of illusion, and doors are surprisingly complex in how they have to interact with every level of that illusion.