People understand the importance of the Malacca straight, Taiwan, and the various islands in that region. It’s the same reason Japan rapidly expanded into that region during WW2, bringing unimaginable suffering to the people in that region.
Maybe you aren’t making this point, and sorry if you aren’t, but that strategic interest does not give China the right to illegally sieze territory to suit itself. That is imperaliam. That is what Russia is doing in Ukraine and it is absolutely wrong.
Why does China not try to make allies in the region
They are both horrible war crimes and should be treated as such.