Ubisoft made a decent effort to support a bunch of extra staff in Black Flag. It most definitely wasn't an upres-job-done deal.
I think you need to temper expectations here. We
know how DirectStorage works and it's not going to benefit any games out there now or releasing soon. Like getting the most out of nextgen games on console, it requires a whole different thought process on how you manage and store your game assets in storage and how you manage asset check-in in-game. Spider-Man loads in about six seconds (4s to menu, 2s to in-game) which is money-f*** ridiculous. Valhalla on PS5 loads in around 40 seconds. That's almost an order of magnitude in difference but requires a completely different asset and I/O paradigm.
The soft barrier on PC is the need for Steam and other game stores to massively enhance the way they handle installs and updates because you definitely do not want to use this new storage approach on 99% of all gaming PCs out there now, whether they're running an SSD or HDD, because it'll result in slower loading. PC games will at least for an interim period, which could last years, need two distinct builds for games and you'll need to patch them differently as well.
I'm not expecting my 3080 to magically make any of my PC games load faster with DirectStorage because it can't. It needs new games to support it and realistically, I'll probably have a 5080 before games are routinely packaging assets for DirectStorage ¯\_(ツ)_/¯