The ohm count refers to the amount of energy that’s needed to power the headphones. Most phones and computers will output enough to power 32 ohm headphones no problem, but not beyond that. The reason your 80 ohm pair sounds bad is because they’re only being partially powered. An amp will power the headphones entirely, sort of like unlocking their full potential. So yeah, an amp will help them sound better because they’ll be fully supplied with energy.

Everyone else seems to be ignoring the fact that you plugged 80 ohm headphones straight into your desktop. They’re not gonna sound good that way. Either get an amp (you don’t need a DAC) or trade the 80 ohm version for the 32 ohm version. I’ve been daily driving the 32 ohm version for like three years and I have yet to find a headphone that sounds better. I haven’t listened to the 80 ohm version personally but from what I hear online the treble is a little harsher than the 32 ohm version.