That's not how reality works. The remaining reactors produced less than 5%. But the money needed to keep them running for a few more years -especially as the shut down was planned for years, checkups and revisions were skipped, no more fuel was ordered- would have come from the same budget that is now paying for grid upgrades and renewable build-up. So keeping them running would have had a minimal impact of a bit less co2 now but a massive damage to the transition to clean energy for the next 10+ years. But that's of course a fact we don't want to talk about in media as that doesn't fit the narrative of stupid Greens having killed nuclear for ideological reasons.
For reference: The shutdown of all but 3 reactors was decided a decade ago, planned for years and came into effect 2 weeks before that new government came into office... the ones they were left with produced -up to their shutdown- ~1,5% of all electricity in 2023. But sure... keeping them alive for the sake of having nuclear reactors (they basically did not have any value other than as a talking point) would have totally made sense... in some alternative reality.