Larian with BG3 laid the foundation to counterfight Bethesda Studio's (Elder Scrolls will have the sixth episode), I can't believe they will stop here to carry out smaller project nevertheless Swen Vincke statements. In addition, will be very important the Wizard of the Coast opinion and PS5 and future Xbox sales.
The story is not so important, you can create a new one (usefull for a BG4 or BG:MMORPG like Warcraft World), but not reaching 20th level will be a suicide towards the community.