I think those networks never figured out how to make money off of it. Without the tracking (and piles of VC cash) that modern social media got, the ads were not worth enough. Microsoft and AOL just saw them as cost centers so when the mobile ecosystem didn’t support their legacy persistent-connection-style protocols they saw no value in investing in rewriting everything.

Piles of VC cash were never necessary, FWIW. Tracking, potentially. They may indeed have massively undervalued ads, or even other monetization options - Line makes millions off of emojis and such, and if they'd have been as big as Whatsapp, possibly billions. Meta too is not even tapping 5% of Whatsapp's monetization potential, FWIW. I wonder if it's intentional to prevent anti-trust concerns.

But I don't think monetization matters too much. Ms tried making the botched Skype play, and as a company there's no way they didn't understand the value of hundreds of millions of eyeballs, daily usage market share. They understood that with IE, despite it being a zero-revenue product in and of itself.

> when the mobile ecosystem didn’t support their legacy persistent-connection-style protocols

You may know more about this then I do - what's the main difference? I used them back in the day and as end-user they felt the exact same as modern messaging apps. I send a message, it gets saved on some server, the receiver gets it from there. When I used it, it definitely didn't require both parties to be online to send/receive.

Or is it about the notifications?