If they're smart they can build support for modern designs, probably small nuclear, as long as they can convince their voter base that the risk of accidents and the problem of waste disposal are much smaller than with the outdated plants they helped close down.
From an economic perspective it's a hard sell compared to solar and wind plus storage, but with the resistance to new windfarms by NIMBYs you can probably justify some subsidies. The timescales involved are still a problem though.
Yes, "Green" Parties are a blight on the political landscape everywhere.
> Restarting or extending the lifetime of existing plants would be political suicide for the current government.
Well, for the bottom of the current "traffic-light" coalition, anyway... (We can but hope.)