You must not have played Witcher 3.
It raised the bar by shooting it into the fucking stratosphere.
I loved Witcher. But the only thing I want Bethesda to learn from it is better writing. But not at the expense of making the story revolve around a set character cause that would ruin a lot of what makes Bethesda games fun (sadly I'm kinda worried that that is the lesson Bethesda took from people complaining about it's writing, that people wanted a more character story centric game from them vs. a world you play in and play your own character. The voice acting and much more set background does kinda worry me about Fallout 4). That's fine for Witcher, that's what CDPR does well and that's the kind of game Witcher is and who it is aimed for are those who want to play a good story and either don't care that they have to rp one character that is already set for them or actually want something more like that (they want to see a character's story rather than play their own).
You know who I want them to learn from, who set the bar for me? Obsidian. Because they took what Bethesda did well, and actually improved on what they didn't. And did a better job with stuff Bethesda is known for (you are a lot more free to play who you want in Fallout New Vegas. In fact more so than any other Fallout. The way they set it up it is the most free to create who ever you want of any of the Fallouts while still having good writing). They didn't make a different game that really is aimed at a different preference and while having better stuff in one area ruins what is good about Bethesda games in other areas. New Vegas was great for the kind of game Bethesda tries to make. You are playing the story but you are making the character and determining what htey story is. They wrote a good backdrop/background and good stories for the ways they could foresee people playing, but the story was till yours to play. It wasn't a set character's story.
Witcher is a good game. But not every RPG should be like it. And it's not the same game as what Bethesda makes. Yes, Bethesda has weaknesses. But if they tried to be like Witcher they probably still wouldn't be as good at what it does well and they'd ruin what they do well (and yes, they do do some stuff better than other companies and few other companies do as well). They're different games. And I wish Witcher fans would realize that and realize that Bethesda has its own strengths. They didn't get a huge fan following cause they don't do anything well as much as some Bethesda haters would like to believe. Maybe they're not what you prefer. But you know what? I prefer what Bethesda makes. Yep, I said it, I prefer Bethesda games (I love CDPR and I want to love their games but I still prefer Bethesda games).