Taril.... that genre switch was never desired by Larian. They've ALWAYS wanted to make turn-based crpgs (always), but industry pressures forced them to go the route of ARPGs. And it was NEVER successful. In fact, it wasn't until Original Sin, when they achieved their first tru, incontrovertible Hit.
Which is why Original Sin games almost sank the company...
Oh wait...
And the overwhelming majority of Larian's fanbase would want an evolution of DOS2 and BG3, not an overhaul.
On the contrary, a VERY large portion of BG3 fans are not fans of turn based games.
It's seen a lot that people mention that they like BG3 DESPITE it being a CRPG, a genre they have no interest in at all.
So, I think you're being unrealistic in what you think is possible, that's all. And again, I have to mention the huge risk factor involved in an overhaul as massive as the one you suggest..... especially when they're at the top like this.
I think you're underestimating just how much BANK they got from BG3.
They literally went from a failing company (As DOS2 was considered a flop due to poor sales performance) into "Yeah, we're now developing multiple AAA games simultaneously"
Lemme ask you: if you were in their shoes, would YOU take that kind of risk?
Absolutely.
I've personally often lamented the fact that most AAA development (Or rather, publishers) have no balls to push the envelope. Instead of doing something new and exciting they're always stuck copying what already worked well before.
Then if I consider Swen himself, he's always given the impression that he wanted to make the games he wanted to make but was frustrated with the lack of success with Divinity that prevented him from doing so. With him seeking out the BG3 IP seemingly entirely due to its noteriety (Given statements about lack of interest in D&D, which is well reflected in the excessive homebrew the game utilizes).
With BG3's MASSIVE success, not only providing ridiculous funding but also making Larian's name well known... He now has his ideal platform for making the stuff HE wants to make, with a good chance of it being successful due to the large following the company now has.
Meanwhile, even if things go awry due to this happening to the Divinity series itself... Well, he already mentioned that after Divinity and the other game that's a brand new IP, that they will work on "Another Original Sin" title. So even if die hard CRPG Divinity fans are upset, they're going to get their new CRPG game eventually anyway.