Trump hates specifically wind turbines (or "windmills" as he insists on calling them). Which isn't to say his administration is friendly to solar projects, but the stuff which makes Trump visibly angry is the wind turbines. The fact this works and is free power is very annoying for a man who insists they can't work and shouldn't be used.
So yeah, Trump doesn't help, but in respect specifically of Solar you'd likely see pretty similar policies from many US regimes, including mainstream Democrats.
Texas is beating California by a large margin when it comes to solar due to bureaucratic red tape and "environmental" review in California along with monopolistic utility companies, which have successfully lobbied against solar by removing net metering and adding in extra solar connection charges.
That isnt an point for california because distributed solar is an economically inefficient solution.
It is only attractive in California due to a combination absurd electricity prices from State sanctioned monopolies and red tape preventing grid development.
Coal is economically inefficient compared with distributed solar.
Nuclear is broadly on par in cost.
The health impact costs of running existing coal plants in Texas are higher than the cost of installing new rooftop solar. That's ignoring carbon costs, which could be the same again.
And that's at Texas install costs. While low for America they are double Australian costs mostly due to poor permitting regulations and lack of competition.
This artificially makes the gap between utility and rooftop solar wider.
So you're being weirdly specific in your desire for economic efficiency.
Followup:
This article [1] and this website [2] contain some information about grid connection statistics by region.
California grid connections approval times are pushing 9 years, nearly doubling that of nearby western states. In comparison, Texas ERCOT operates on a connect and manage framework, which lets people buildout generation without stagegate approval, and then works out the interconnection issues in parallel or after the fact.
From what I can tell, Trump mostly doesn't like them because you can see some from his vanity golf course in Scotland. He has absolutely zero interest in the significant benefits they provide, he only cares about the fact he can see them from "his" land.
I remember when the first ones started appearing in the UK over 30 years ago and people were quick to complain about how ugly they looked. But actually, over time I think most people accept them now, and personally I think they're pretty cool. Most of the UK ones are actually off shore now - you can just about see them from the coast, but they're just small specks on the horizon at that distance. I think the biggest concern people have with them now is the belief that lots of birds get killed by them, but the reality is that actually many more birds die every year from flying into windows than get hit by turbine blades.
So yeah, Trump doesn't help, but in respect specifically of Solar you'd likely see pretty similar policies from many US regimes, including mainstream Democrats.