"The most advanced protocol" counts for fuck-all if the actual client is missing features compared to the competition.

Whatsapp: 1) Install 2) it works. Even my 60+ relatives can handle it.

Discord: 1) install 2) it works. It also has voice/video chat rooms and a huge ecosystem of bots.

Telegram: Works, has bots, channels can be moderated, sticker packs, gifs etc fun stuff.

Whatsapp: Sends all phone numbers on your phone to a third party.

Discord: Works as long as Discord does not run out of VC money.

Telegram: Sends all phone numbers on your phone to a third party.

What is your point? That Matrix can never be popular as a phone messenging app because it doesn't collect phone numbers, and doesn't raise VC capital?

Whatsapp is the worst chat system I use. It doesn't support reactions (which are essential if you don't want a chat with many people to devolve into incessant pointless notifications), nor does it allow easy editting of the message you just sent (another essential feature, given how often small mistakes can totally change the meaning of text). I can't collapse pictures/gifs that annoy me, I can't chat with people on other services. It won't let me use whatsapp web on multiple other devices simultaneously, it won't let me use whatsapp web when my phone is out of battery (the exact time I most need it!). I can't invite people to chat with me on whatsapp without them having to create an account and give up their phone number (and usually their contact address book too).

It's very strange to me to hear people describe Whatsapp as having good UX.

WhatsApp has good onboarding and brand recognition. (YMMV, this is highly dependent on which country you are in). You don't need to create accounts or register. You just need to know your phone number.

Having to give up your phone number and contacts is a feature for most people. They can instantly see that Marge from the office also uses WhatsApp so they can call/message them using that instead of paying for calls and SMS.

The limitations of WhatsApp web are mostly due to it being end to end encrypted. The "web client" is basically just using the phone as a proxy. It _is_ possible to have E2E encryption and allow multiple separate clients, but it's not a trivial problem to solve, thus most won't do it. (Telegram's E2E chats are device to device and not available on other clients than the one that initiated the connection.)

It's still crap, don't get me wrong. I'd rather use anything else, but at least where I live, it has critical mass and is the de facto standard.

I don't disagree with what you've written, but a chunk of it is exactly what people are getting criticised for elsewhere in this thread - giving a technical reason that I as a user probably don't care about for bad UX.

> it has critical mass and is the de facto standard.

Yeah, it's the critical mass thing that is the most significant reason here, although it originally caught on back when simple onboarding was very unusual and that was its killer feature.

All three of those services are centralized though. I'm talking about things I can host.