From me for example. I follow this studio and team since many years and i’ve participated to the funding of Divinity: Original Sin (DOS) more than a decade ago…
They got money from several sources but mainly because (or i should say thanks to) they delivered good products, they have being able to survive and work on BG3. Luck is not the reason, they’ve worked hard to achieve that…
It’s opt-in if i remember well and you can avoid sharing it with 1 click in the options.
For the devs, that help them a lot to tune the difficulty of the game in some sectors and find what to improve… For once it’s not to sell you something, just to improve our experience.