You have
no idea how utterly shit the mic inputs can be on inexpensive USB audio interfaces. On the very budget end you can usually take your pick between something with half-decent noise on a dynamic (but perhaps not entirely distortion-free on a LDC) and something that sounds fine on a condenser but ranges between rather noisy and flat out terrible on a dynamic. The latter variant is usually courtesy of some sort of lowish-noise opamp like an NJM2068. (Those much worse than -120 dBu usually have some sort of constructive issues, like the notorious Audiobox USB 96 which seems to have a noisy virtual ground.) That used to be the standard performance level before people (presumably at Focusrite) figured out that you could press an NJM2122 into service with decent results.
Excuse the test
en allemand (machine translation advised), but listen to the SM7B sample:
ESI hat zwei neue Audiointerfaces im Angebot. Wir haben die kompakten und preisgünstigen ESI Neva Uno und Neva Duo für euch gecheckt!
www.bonedo.de
Utterly horrifying. It sounds like a cheap headset mic or something. My guess is that it simultaneously runs out of amplifier GBW and low end at high gain (the capacitor in feedback tends to be 1000+ µF and this may not have fit, neither the case nor the budget), all while having substantial amounts of input noise.
You will have noticed that the majority of interfaces do find themselves between about -127 und -131 dBu(A), which is a much more sensible span of about 4 dB. Modern constructions beyond the absolute bargain basement price range generally are at least decent, thankfully.