A nuclear plant would take the best part of 20 years to build and has at least a 40 year lifespan. It'd be competing not against today's solar and batteries but against 2040's solar and batteries on day one. And it'd need to be profitable until 2070.
It would have been great to have invested in nuclear in the 80s, but we didn't. Like hydrogen cars, it could have been great but we've moved past it already.