The researchers used past weather data (as you wrote), and looked at how that would work in a future (as I said) energy-mix scenario: a climate-neutral energy mix as projected for 2045.
So it definitely does not refer to the energy mix as currently installed.
Where did I claim anything about the currently installed energy mix?
I claimed that no wind and no sun happen very seldomly across Europe.
The aspect of the 2045 scenario is irrelevant here.
Btw. it's important to note that there are more renewable sources besides wind and sun: heat from the earth, water (e.g. rivers, tides), bio gas, ...
So it definitely does not refer to the energy mix as currently installed.