I was heading to these forums to open a topic about what I thought was this potential issue; I didn’t anticipate it would have occurred already - not least four times!
Because the links are “guessable”, it’s too easy to be wrong; because there’s no verification, it’s too easy to go through with it.
IMO in the absence of an integration with say Keybase (and perhaps even then) to verify where you want to be sending money, a randomised link is actually preferable. Someone won’t get jh32jk5ms34s9 wrong, because they’ll check it every time instead of thinking they remember it, and forgetting there’s a numeral due to a name collision, or that I’m full name not nickname, middle name included, etc.
I think it’s only a matter of time before this goes properly wrong, and somebody complains that their money didn’t arrive. (cc @anon50039658)