I mean they have a ton of different stamps (and you can find older ones, too) - but you have to dig to find them, they rarely appear in your local post office: https://store.usps.com/store/results/stamps/
Not really a fair comparison since those USPS examples are all "extra postage" stamps that you only use if you have oversized letters or are trying to use up old stamps. The equivalent Royal Mail stamps are even less imaginative - just different hues of the same drawing of the Queen[1].
