https://en.wikipedia.org/wiki/Nuclear_power_in_Germany#/medi...
Also:
https://www.destatis.de/EN/Themes/Economic-Sectors-Enterpris...
Nuclear power is mainly being replaced by renewables, not coal or gas.
Natural gas only accounts for 15% of electricity production, the upcoming gap could probably easily be filled with alternatives.
But it's main use isn't electricity, but for heating in private homes and all sort of processes in the industry. About half of all homes are heated with gas, you can't simply flip a switch and replace the gas heating in 20 million homes with electric heating.
TL;DR: the pressing problem that needs solving is how to prioritize private homes versus the industry's use of natural gas, even if nuclear power plants would suddenly spring out of the ground for free, they wouldn't help much with this.
Gas isn't a transition to anything.
New plants only qualify as "green investments" if and only if they can be used to burn electrolyzed hydrogen in the future.
Even if you want to shutdown nuclear, Germany did it in an extremely stupid.