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?