Be careful, or you'll summon one of the many locals here who have been very successful in AI and lisp. For example @marklwatson has a number of books on modern "AI" applications in various lisps (I particularly recommend checking out Hy, since it's so easy to move from python).

If you're talking about AI winter, it might be fair to put some blame on the commercial Lisp Machine producers, but I think it's indisputable that the early failures were due to capricious government funding as well as the non-existence of big, cheap GPGPUs.

Lisps existed long before any AI hype, and they'll happily continue long after.