I think the success of early access will help ensure they do finish the game and get it to completion. Imagine how difficult it would be to spend all this money on years of development with no income. With the income from early access it takes a lot of the financial pressure off.
I think any big project like this runs the risk of getting rushed at the end and quality falling off, but given what we've seen so far, and Larian's track record, I think we'll get a good game. I also think there will be a lot of BG lovers who will not be happy with the final project no matter what.
I actually bought the game twice (I tried Stadia and didn't like the experience, not Larian's fault) and given the number of hours I've spent enjoying it, I'm already pretty happy with the investment.
