The types of people who change the world through their research or at least make huge progress tend to be the type who naturally focus on and become outright obsessed with a particular unsolved problem, technology or idea.

I think a large part of my lack of enthusiasm comes from my belief that advances in artificial intelligence are going to make human-run biology irrelevant before long.

That may be true, but if so it can be viewed as an opportunity just as much as a threat. If you believe this then go learn some AI - your background in bio could give you a unique perspective. The modern world is all about dual/multi class.