The storage problem is the limiting factor. Batteries are wildly too expensive, pumped storage takes a huge amount of space and isn’t feasible in most places due to geography, and hydrogen is not nearly there yet technologically.
If we switched entirely to wind and solar we would need to accept total shutdowns when we had a bad run of weather.
For things like house seats where there are a dozen or more positions, proportional representation would probably be better. Unfortunately that system is so foreign to Americans I think it would be a tough sell.