The plant was not broken and it could absolutly be turned back on. They would just need to catch up on some delayed maintance.
Nuclear 'waste' has plenty of solution and all these 'but the repositoy' is just what anti-nuclear people use to scare people that don't know any better. Nuclear 'waste' doesn't need a repository, its perfectly fine to just store it above ground for as long as needed.
The Asse mine is completely irrelevant to the discussion as this is not how anything is done anymore for a long time and many countries have proven capable of managing waste fine, including Germany since then. The fact is, basically nobody has died from waste managment.
Asse risk is overplayed, even if nothing was done, the likelyhood is that in the next few 100 years nobody would die because of it it. They are removing it because maybe in a few 100 years there could be a slight impact on ground water. Even the is if you make some worst case assumtions. Spend the billions it would cost to empty the mine on gold and put it into the ground. People in few 100 years can dig up and spend on what they think is their most important problem. In the incredibly unlikely case that its radiation, they can use their technology to do what they think is best.
Again: How can it be turned on, when it is actively decommissioned ("Rückbau") since 2024?
What are the costs (without omitting storing radiactive waste securely[1] above ground for some thousand years ? Are they less than batteries + solar + wind?
[1] think terrorism, drone strikes, ...