Starship is very fast, taking only a couple of milliseconds to gather the data (and you can easily configure it to minimise what it'll spend time gathering). It's night and day compared to other ones I've tried, where the hundred millisecond-ish delays annoyed me.
100ms to render a prompt are meaningless. You can just type commands and run them asynchronously. I do this all the time when a previous command is taking a little extra to complete but I already know what my next command is going to be.
Depends a lot on the system. I tried using it on Windows via MSYS2, and it seems like some Windows overhead (maybe process startup?) was causing Starship to slow it all down to a crawl. Disabling a few of the addons helped but didn't fix it. In the end I stopped using it.