As far as I know, this is not true. On a small scale wind has been profitable for a long time. In The Netherlands, small scale commercial wind turbines go back a long time. As far as I know there were no subsidies back then.

There's also hydroelectric power, with a very long history of being economically viable.

Economically viable because the costs of the land used behind the dams were not nearly as high. Today most of the good places for hydro are already taken, and we have far more concern for the environmental impacts. There is still room for adding hydro, but it isn't as easy as in the past.

Hydro is being phased out in the USA because it destroys river/watershed biomes. You won't see any significant hydro being done in the USA for quite a while as the environmental groups won't allow it and it will be locked up in court for decades.

Not true. Technology is making breakthroughs because that is what technology does. Solar and wind may not have moved along quite as fast but they would have moved along. We need nuclear for stability (as we don't have energy storage facilities that can handle extreme weather events for days or weeks) and we need solar and wind because who can afford to give up "free" energy that is there for the taking. Solar is the end goal (or fusion) of course but energy storage density at grid scale is decades off. There are several viable nuclear designs available now that can't go critical and are practical with just a little more work and government support.

> We need nuclear for stability (as we don't have energy storage facilities that can handle extreme weather events for days or weeks)

We also don't have the nuclear reactors that would supply that energy (particularly at global scale, where breeding would be needed). Why is building those reactors conceivable, but building energy storage systems not?