I don't really get the MUP hate, not all of them are the same. If someone has a long wide MUP that rarely ssees traffic why not use it? I've been on both kinds and ride accordingly. IMO mups have a time and a place, recovery rides or out with the gf.

Sometimes "people watching" is fun in Mups. Our
mup is loaded with hot chicks, some even cycling so I use it as a place to meet people and exercise at the same time. I don't always need to be training when on my bike, sometimes I ride for leisure. Still 20mph responsibly on an MuP atleast around here iis no problem.