I like the the Greens, but they actually initiated the phase out the last time they ruled 20 years ago. One of their core ideologies was the opposition of nuclear power.
But they were also for a coal phaseout. They aren’t responsible for how atomic plants got replaced and that the phaseout got changed into specific dates, they implemented a more flexible phaseout.
A later government decided to slowly replace coal plants with gas plants and keep those coal plants in standby for emergencies for some time. Which is what triggered last year, as those standby plants fired up again when gas plants became unreliable.