This is what I'm saying and what people who recommend containers as a "replacement" for profiles sorely miss.
>20 minutes to set up
Meanwhile on Chrome this just worked out of the box and didn't have UI that's been abandoned for a decade.
The bigger problem for me is that (at least when I last tested Chrome profiles -- it's been a while), there was some browser config that was shared between profiles. Maybe extensions? I don't recall.
This was unexpected and undesired, so I went back to Firefox.
Anyway, there's no benefit to Firefox or its users if profile switching is ugly or clunky. They're improving this and that's a good thing for everyone.
I add an icon (slightly modified for each profile) to the script, and rename it to (e.g.) ~/Applications/Firefox-work.app for convenience. Works from the Dock, Finder, Spotlight, etc. I usually launch from the command line, but all the usual ways do work.
Improving the profile switching experience is great of course. But the above workaround has served me perfectly for as long as I can remember. Obv would not work for everyone.