Earlier quoted context omitted.
This is the whole "linux desktop isn't there yet" thing but with phones now. It's not shiny but it does work. Continuing to use abusive software is a disservice to yourself and everyone around you.
MMS doesn't work on any FOSS non-Android Linux phone I'm aware of, so they definitely do not work for a significant percentage of the population even for basic group text messages. Building an alternative phone OS is much harder than building an alternative desktop OS—the requirements are much higher (battery life, cellular, app support) and the mobile web is far less developed as a stopgap compared to the desktop we…
I think it would be good to point out that MMS often doesn't even work on android phones. So making that a requirement is a bit silly.