This lead to a much higher market share for Android and the need for a cross platform messenger. While SMS were cheap or included in your monthly plan MMS was not and was really expensive. Except if you communicated with someone in another country. This meant paying expensive roaming fees (these are basically history thanks to the EU).
Meanwhile WhatsApp was "free" and a way better user experience for group chats and sharing media than SMS and MMS. It was also a way around roaming fees because you could use it with your included roaming data or over the hotel wifi. So it was basically universally adopted in the 2010s. Sending a WhatsApp is basically a verb today.
This is of course all anecdotal and is mostly a western European perspective.
I think this is all stupid. One the one hand the tech companies get slammed for not inter-operating, then Apple gets slammed for inter-operating. Loads of phones have come with vendor specific messaging apps and such, it's just that Apple committed the crime of making theirs decent and successful.
Come to think of it, the same lack of interop openness applies to airdrop, use of the on-phone NFC chipset (for uses other than apple-pay), and a bunch of other such things.
I think it's more to do with cross border communication (roaming / international charges) that were and are quite costly.
Imagine if you would have to pay international charges when communicating between states in the USA - that what's happening within EU still.
Thus rise of Internet based IMs where you are not bothered by the regular gms cost and use whatever data data transfer, which is free/cheap