That is a problem. The only way it could be worse is if your technology required a constant supply of input from a foreign country...

From a geopolitical standpoint running a country on locally produced renewable power is obviously the least risky approach, even if you get cut off from further expansion of your renewable production.

This is normal business. Suppliers change due to all kinds of reasons. If you are planning any major build and you haven't also planned contingency cases, including alternate suppliers, then you are not qualified to be in charge of such a build.

And it's not like you cannot find good alternatives outside of China. They may be more expensive, but they exist (and are high quality - Germany).

That's certainly an issue, but much, much less critical than gas.

Are people really suggesting the opposite: that the renewables transition should not occur, and the EU should continue to burn gas from more and more desperate sources, until it can be onshored?

Solar panels are piss-cheap to make. They are literally just glass with a transistor on them (huge oversimplification)

All of the materials used are readily available and manufacturing is not incredibly difficult. Inverters and control circuitry is way more of a risk than the panels themselves but there are stockpiles and sources that are good for many places

That's nowhere near the level of dependency that fossil fuels bring.

Barring significant damage, you can maintain approximately your current level of power generation for years at a time without more than routine maintenance.

Fossil fuel power requires constant input of, well, fossil fuels.

So while what you're saying is true, it would be a ludicrous stretch to say that it brings solar panels within a few orders of magnitude of fossil fuels in terms of dependency on foreign powers.