Well, the BG3 EA has certainly coincided with WotC reviewing their revenue opportunities - sorry, I meant reviewing their rules-set.
Each may have influenced the other; only the companies involved know that. As both companies seek to address larger audiences, they also need to broaden the appeal of their products, which generally means making them simpler ( more accessible ) and more inclusive ( to avoid upsetting people ) and more configurable ( to appeal to different audience demographics ).
WotC will certainly have taken note of the feedback for BG3 and discussed changes to the ruleset with Larian, but BG3 at release will be like the earlier BG games - a modified version of existing rules. It doesn't really matter if the TT rules change subsequently, the game stands on its own merits. If there is an expansion or significant future game update ( which Larian are known to do ), and the TT rules have changed, then maybe there will be changes and re-branding; particularly if it's good for marketing.
I'm not sure how much it matters. If you don't like BG3 now because of the 5e rules, you probably won't like it under any likely future ruleset.
