Modern branch predictors absolutely have neural nets these days. Check out for example this 2001 IEEE paper on "dynamic branch prediction using neural networks": https://ieeexplore.ieee.org/document/952279 or this 2007 patent using "conditional bias" (it beats around the bush, only explicitly naming neural networks once, but it's clear what it is about if you read between the lines): https://patents.google.com/patent/WO2009066063A1/en.

There is a wealth of patents and articles if you search for "neural net branch prediction patent".