This is basically correct. FERC policies / interconnection queues are currently the biggest thing holding back additional renewable growth. Last I was looking there was something like a terawatt of solar projects waiting for interconnection nationwide. I'm not sure how much this effects California specifically but I believe it does.
The essential issue is that most utilities have a policy that's sort of first pass the post. The first major infrastructure project, including generation, which would render the grid over capacity needs to pay for those grid capacity upgrades in order to get their project permitted. Which a lot of these projects can't afford, so the queues just become really chaotic whenever someone loses that lottery draw. And the queues can be absurdly long. Years not months. Many projects might not be able to afford those kind of delays.
Particularly painful for tribal entities. I know there were several major wind projects in the middle of the country that got fully funded and planned out and then killed by those queues.
The dumbest part is that a lot of these grids actually do have adequate capacity but the lack of proper monitoring equipment - which isn't even very expensive to install - that could trigger curtailment for those extremely rare over capacity events prevents using the grid at its real capacity.
There are some pretty deep issues with most utilities for why this happens. The short of it is that are huge misalignments of incentives in the public-private partnership contracts.
Solar in particular is so cheap that if the free market were truly allowed to build as much of it as it could bear it would probably wipe out most fossil generation. It's probably for the best that we don't allow that kind of crazy free for all for a lot of reasons, but it's notable that fossil electric generation is basically guaranteed to decline even if just for purely economic reasons going forward.
If you want to advocate for this policy look for if you have something like a Public Service Commission. This is one of those things like City Council or an MPC - if you have an elected PSC they probably don't actually hear a lot of constituent voices meaning if you reach out to them you will have an outsized voice.
Smart transmission technology and reconductoring are two examples of fairly cheap grid upgrades we aren't really making that could vastly increase short-term capacity. But the main thing we need immediately is permitting and other bureaucratic reform.
