I wonder how many areas there'll be in the final game if the max lvl will indeed be 12/14, since lvl 6 is be pretty attainable by the EAs' end. Maybe they just sped up xp gains for right now.
I don't see any reason why Larian wouldn't be willing to do a sequel linked to the original story and a higher starting level unless they feel it would make for a difficult entry-point for new players.
I feel like they would most assuredly feel that way. Nowadays everyone tries to make sequels super-accessible to new players, and throwing them into a lvl 12 character with all the abilities/passives that come with that is pretty against that.
Different people - different tastes, I love the idea.
Being thrown into the deep end straight away feels more rewarding to me personally, thats half the success of a game like Escape from Tarkov which isn't really thrown around in comparisons, but still has an amazing game design. The players become more invested when they have to learn everything from scratch, thats what it felt like playing the original BG games for me, I never even heard of the universe or the tabletop rules up until that point. I was lost in wonder.
People these days like being handed things, everything must come easy. I lose interest pretty quickly when something is pandering to me.