What you’re missing is that factories were built in Ukraine as a part of reconstruction after WW2, but engineers were mostly Russian, relocated from Russia.
These days pretty much all Ukrainian space industry is dead, and it was dead even before war. Most competent people left for Russia or USA. Yes, they still provided some components just because it was cheaper to build them in the original factory, but in a last few years Russia just replaced all Ukraine components. Antares had Ukrainian fuel tanks I believe, but I doubt it’ll last long.
Regarding engineers, I don't think that's true at all — as a simple example, two of the three lead engineers on the Soviet space program were from Ukraine.
These days pretty much all Ukrainian space industry is dead, and it was dead even before war. Most competent people left for Russia or USA. Yes, they still provided some components just because it was cheaper to build them in the original factory, but in a last few years Russia just replaced all Ukraine components. Antares had Ukrainian fuel tanks I believe, but I doubt it’ll last long.