IMO it depends on the system, and they are buggier in different ways. I’ve never not been able to play 76, but New Vegas would just shut down, or freeze, and you’d lose a bunch of stuff. Even 3 I still have never played the alien mothership DLC because it just wouldn’t let me. I’d get to the beam me up part, and it would freeze every time. I’ve also only played it on playstation, I’ve heard less issues with other systems.