While I agree a lot of open source messenger services have terrible UX, I don't think "the masses" care about it that much. What matters is what everyone else is using. People are using Snapchat or Instagram Messenger and I haven't seen a single person who likes the UX of those services - they just use it and put up with hatred for it because that's what all their friends use.

MSN Messenger had tons of open-source clients back when it was the popular IM network, and it was a weekend or two of work to write a client for it.

Open source has nothing to do with this conversation.

I’ll bite : how does open source have nothing to do with a comment discussing “freedom oppressing software” and “Stallman”?

To be honest, I couldn’t imagine a word more related than "open source". Isn’t that junction literally the acronym F/LOSS?

I think this is purely first mover advantage. We get stuck with bad products simply because those were the first products on the market. It is difficult to change them once everyone uses them. The same applies to the adoption of IT on the banking industry. Now we are stuck with COBOL and systems that are hard to migrate without damaging the economy.