If you're browsing with a browser, then there are 1000 ways to identify you. If you're browsing without a browser, then there is at least one way to identify you.

I think what they meant is: there’s already so many other ways to fingerprint (say, canvas) that a common user agent doesn’t significantly help you

'There's so many cliffs around that not jumping off that one barely helps you'.

I meeeeeannn... sure? I know that browser fingerprinting works quite well without, but custom headers are actually a game over in terms of not getting tracked.