I don't think that they do. How you think about and prepare to play a game is entirely different than the rules you use to adjudicate it. OSR doesn't have a monopoly on style, or challenge, or opened ended games. You don't need to use an OSR rules set to have a proposition filter on your game that validates players making highly improvisational, open ended, and fiction specific propositions. "I carefully push aside the curtain with my 10' pole." is not a rule set specific proposition. It's just a way of approaching playing a game.
All the rules do for you - all any rules do for you - is provide a tool kit for handling how those propositions turn into new fictional positioning. You don't need old and busted ideas about doing that in order to run an old school game. I don't need another table argument about how infravision works. I don't need another table argument about what the chance to detect an invisible creature should be. I don't need to wrack my brain for whether or not the PC should drown. None of that is essential to running an old school game. That's warts of an old school game. That's the part I'm more than willing to leave behind. But the parts that I love, I can totally take with me. I don't need to give up any of that to use a rule set with functional skills and environment rules and a clear set of general fortune tests that are applicable to generic situations.
When someone says "old school games play absolutely fine" it really makes me wonder if you played them. Like as soon as I read the 'scent' rule in 3.0e, I smelled the 1980's and the old pizza and the table arguments as we tried to get realism and the rules to mesh into something everyone at the table agreed to. And if that didn't happen for you, where you even there?
Oh they most certainly do.
I still play them (I run a B/X game every Tuesday to a full table). I enjoy them. I'm perfectly happy running and playing B/X and its clones. They work perfectly fine for me.
I don't know why you have to come in and tell me the game i enjoy is old and busted or I don't actually play them.
You are certainly welcome to enjoy the games you like. As I said there are tons of games that fix the problems you have with OSR games.
Happy gaming.