Electric improves the flexibility of BRT, for one - you can run buses underground with lower ventilation requirements and without running overhead cables. Extrapolate "better BRT" to whole highways and dedicated streets running articulated self-driving buses(a far easier task than open-road self-driving) - and you can achieve a lot of the things that rails do, for cheaper. The things that can't be done with that model, the biggest capacities and the highest speeds, are the things that are most in need of a huge subsidy anyway.

Electric is also giving ferryboat transit a new lease on life in terms of energy cost/emissions impact. The SF area fleets have ordered a few electrics already - and they've been expanding service, adding new terminals. It's a return to an older model for regional transit and it has plenty of upsides, with the big caveat of needing a viable coastline.

Between those two, I think you have the model for a lot of future transit infrastructure. Regardless I would also not claim rail is "doomed".