They dominate the market, have Germany split up amongst them and are crying and threatening with job losses at the slightest sign of change.
Interesting fact (taken from the linked Wiki article): Those big four had less than 10% market share in renewables in 2013. Not sure about now, but numbers might not look much better.
They are the ones that operate coal and nuclear power plants and are not interested in any change whatsoever.
[1] https://de.wikipedia.org/wiki/Die_gro%C3%9Fen_Vier_(Energiev...
The renewable fraction in both cases is just over 30%, but the UK has managed to phase out coal in favour of lower-carbon gas. UK prices average around €0.14 per kWh. Maybe the difference is made up by wind, but there Germany has a huge domestic champion: Siemens.
https://www.cleanenergywire.org/factsheets/fighting-windmill...
https://www.dw.com/en/germany-protesters-oppose-suedlink-win...
There is less resistance to offshore wind projects and to small scale distributed solar. Both of these generating resources are more expensive than onshore wind farms.
Even in the matter of distributed solar, note that the peak installation rate was back in 2012:
https://en.wikipedia.org/wiki/Solar_power_in_Germany#Generat...
Germany not only installed a lot of a particularly expensive kind of renewable capacity (distributed solar). It did most of that installation some time ago when it was even more expensive to install. And it did so in a very sunlight-constrained climate, so each kilowatt of capacity generates much less energy than in Italy, Spain, or the US. Since industry threatened to just relocate if higher electricity costs were passed on, residential and commercial electricity customers have borne the financial brunt of the renewable buildout while heavy industry was spared.
The UK did better by phasing out coal in favor of gas faster than Germany and not installing significant solar capacity until the hardware had become much cheaper. The UK's renewable additions were almost exclusively wind until 2011. The UK started deploying significant solar several years later than Germany:
https://en.wikipedia.org/wiki/Solar_power_in_the_United_King...
Between deliberately choosing to pioneer solar PV installations in a low-sun country, phasing out nuclear power, and acting to placate the powerful domestic coal lobby, Germany has really spent a lot of money to accomplish a very modest degree of decarbonization.