It isn’t strange to use your non-dominant hand for things, no. Maybe most people do lean toward using their dominant hand for everyday tasks, but I think it’s a matter of habit for most things. “Non-dominant” doesn’t mean “nearly useless”.
I would say it is a bit strange for your friends to pay a lot of attention to which hand you use to unlock doors.
It’s probably not 100% necessary; even Ratchet & Clank: Rift Apart (which was designed to use the PS5’s fast loading speeds to switch between worlds on the fly, and supports the latest DirectStorage implementation on PC) can be played off a hard drive, tests have shown. But any PC recent enough to play Starfield on really should have an SSD.