Exactly right. This is another way of saying they generate NO baseload power, since you cannot count on them being available 24/7/365 like coal, nuke, hydro or natural gas.
But wait, there's more! Solar and wind can't be relied on for demand response, either: you don't know if they can generate enough at the time of the demand. (Solar is usually better about this than wind.)
So, it's just "green" unicorn fart power that nobody can count on. Without the subsidies, every last grid-tied wind project would be torn down or abandoned.
One thing hydro does that no other energy source can do is create property value. Lakefront property sells for considerably more than swampland. My little town and the dam came into existence at the same time and the town grew as a result of the dam. In fact, my house sits on the site where the icehouse once was. The ice house wouldn’t have been here without the lake.
The dam was originally built to mill grain and was later converted to electricity until it was decommissioned in the 50s.
Individually, coal, nuke, hydro or natural gas do NOT run 24/7/365 - more like 24/7/340. They rely on each other to run during peak load or scheduled maintenance, just as wind would rely on one of the other forms of generation during low wind periods. And during high wind periods, if wind energy is cheaper than a natural gas peaker (most wind is), why not take the wind energy?