I agree that Energiewende is important and that reducing the cost of renewable was sorely needed, but at the same time the decision to close the nuclear plants (rather than coal) was a gigantic mistake.

1) Because it costs a lot of lives. Coal + Lignite in Germany cost 8000 lives per year (funnily everybody also seems to forget that coal release more radiation in the air than nuclear plants).
https://www.thelancet.com/article/S0140-6736(07)61253-7/abst...

By contrast Chernobyl was 4000 deaths
https://www.who.int/mediacentre/news/releases/2005/pr38/en/

By not closing 10GW of nuclear production, Germany could have prevented 2000 deaths by year, so in total 20000 deaths over ten years.

2) Because it gave the impression that a carbon free electricity could be achieved by wind and solar alone. This is not the case: first Germany will only close coal in 2038 (in 20 years!!), and plan to use gas to replace coal at least up to 2050. Gas is way better than goal for air health, but it still release a lot of CO2. 2050 is way too late to be carbon free.

The problem with wind and solar is the intermittence: if you look at the data from
https://www.cleanenergywire.org/factsheets/germanys-energy-c...
you will see that on average wind is at 20% capacity and solar at 10% capacity. So even with batteries to smooth things out (which don't exist at the huge scale we are speaking with), Germany would need a lot more solar and wind that it does. For a peak consumption of around 70GW, this mean it would need 350GW of renewable energy. It is so far only at around 100GW, having added 50GW the last ten years. So at this speed it would still need around 50 years. This is without counting the fact that:
- the energy stockage problem is at least as hard to solve
- solar panel and wind turbines have a lifetime of 20 years, so this does not take into account replacing existing ones
- it is getting harder and harder to find place to put them. In 2018 the rate of installation of new renewables slowed down a lot because of this problem.

3) By contrast nuclear cost less, when taking into account this intermittence problem and the cost of interconnection (which is not counted by the figures usually given); it is a lot easier to interconnect a huge centrale than a lot of small ones. But cost is not an argument anyway when we are talking about climate change (if there was a proper carbon tax at least Germany would have closed coal before nuclear).

It is friendlier to the environment (wind turbine kills a lot of birds, and solar panel take a lot of room from wildlife).

It is as safe as solar and wind, and way safer than hydroelectric and coal.
Banqiao Dam collapse was 230000 deaths. Yet nobody is calling for stopping
hydroelectricity.

Again, Chernobyl was "only" 4000 deaths (high range estimate using a linear
model rather than a threshold model are at 10000-20000 deaths), Fukushima
was 0 deaths (but 1500 due to the evacuation, including zones where the
radiation was the same order of magnitude of the natural one). Chernobyl
cannot happen with modern reactors; a Fukushima style incident could, but
the nuclear operators increased the security of the points of failures that
Fukushima revealed. Again, living near a dam is probably less secure than
living near a nuclear plant. And building and installing solar panels and
wind turbines cost lives too (as do building dam and nuclear plants, and so
on); on average as much as nuclear killed. Yet there is a lot of hysteria
about nuclear plants, because an accident is so much more spectacular and
visible.

And yes an accident would leave an exclusion zone, but it would actually be
smaller than this stretch of no man land (a coal mine in Germany):
https://twitter.com/LejeuneXa/status/1124749045996634118

4) I am not saying nuclear fission is a miracle energy (fusion would be).
It is as safe as it is in developed countries because of all the
regulations, this model would not be applicable in developing countries.
For these countries, wind and solar is the way to go, and in this respect
Energiewende which paved the way is a success.

There is the problem of nuclear waste, but this frankly this is a (small)
problem at the scale of 100s of years, this should not at all be our
priority given the very small time frame we have to reduce climate change
(the ship has unfortunately sailed for preventing it from being too
impactful [aka more than a few million deaths], the real question is
whether we limit it to be really impactful or a total catastrophe). This is
like worrying about a leak in the sink when the whole house is on fire: bad
priorities!

5) But, by making the illusion that 100% carbon free electricity could be
achievable without nuclear, Germany set a dangerous precedent. It is not
currently possible (as proved by Germany not really reducing its CO2
emissions), it may be possible in 30 years (current prevision is only a cut
of 65% in 30 years, the 95% cut is from a very optimistic plan by
Greenpeace) but this is way too late.

By refusing to use nuclear for purely ideological# reasons, Germany is
depriving itself from a vital tool against global warming. And by
vindicating some green movements to call for the closing of nuclear plants
along the development of renewable (whereas the sane thing to do would be
developing nuclear along renewable: solar panel in sunny places like
desert, offshore wind turbines and nuclear plants), it may indeed have done
a whole lot of harm. And when we are speaking about the future of human
civilisation, this may prove to have been indeed a very costly mistake
indeed.

[#] And yes, when you take into account that coal each year kill more in
Germany than Chernobyl did globally (and way more than Fukushima); and that
even if there was a Chernobyl every 10 years (which cannot happen with the
nuclear reactors we have) anyway it would still be a drop of water compared
to what climate change is going to bring us, closing nuclear plants can only
be ideological.