You're wrong. Well, calling you are wrong and then answering: you are wrong
Wind turbine output is wind speed cubed. Depends how you want to say that. Ofc. it is not speed cubed. It increases with the cube of the speed, perhaps you meant that
So a tiny wind speed generates a much larger % in power output. No it does not.
You have "rated" speed. For easy math we can just take 10m/sec as rated speed and assume the turbine generates 1MW at that speed.
Now you double the wind speed to 20m/sec, the wind turbine will generate 8MW.
Now imagine a "square" function graph drawn, just use a simple sheet of paper, you see from 10 to 11 and 11 to 12 etc. the "square" has no real effect, it is below "linear" increase, the huge jump is at the right side of the graph.
That's fairly trivial to handle if your grid have a lot of very powerful load following sources
Actually: every grid has that, or it simply would not work at all.
but that will make wind+solar getting over 50% of your grid production pretty much impossible without very advanced energy storage, ideally a power source that can be charged/discharged very quickly.
And that is simply wrong. The solar production you can predict EXACTLY so you know how to plan in your "conventional" plants. The wind production can also be predicted easy enough to easy let your conventional plants follow to fill the "balancing" gab. Actually all countries with a high percentage of renewables do that already.
The only problem is the "mentally" problem of wasting surplus energy, because you shut down parts of your wind farm if you really produce excess energy.
Having extra storage has only one benefit/effect: if I store energy today, I can use it tomorrow instead of a conventional plant, so I safe fuel (what ever fuel I use). The grid is otherwise completely unaffected.
Neither Denmark nor Germany built any special storage the last 20 years to cope with the grows of renewables.
The question basically is only how green you want to be and how quickly you want to jump to 100% renewables and how to invest your money. As long as legislations _allow_ you to run a coal plant, you simply have to figure yourself: is it cheaper to run the coal plant and spent the fuel, and have it shut down/powered down half of the time, or is it cheaper to build up storage and replace that plant with stored surplus energy. The decision is simply monetary
Bottom line the idea spread here on