Those were not simple, seamless, cross-platform, drop-in replacements to SMS though, which is what OP was referring to by “text messaging.” Sure, clunky systems which had no chance of mass adoption existed before.
They were if you're willing to overlook the requirement -- which WhatsApp shares -- for the other person to use the same app. (Well, protocol. Gaim handled AIM and MSN fine.)
The only thing SMS offered was that the other person didn't need to be running anything. WhatsApp didn't offer that, and also didn't improve on the other messengers of the day.
You’re missing the fact that WhatsApp was actually available for essentially all phones (even in 3rd world markets) and that nothing else is needed. AIM and MSN required an email address which means you need one, as well as an email client on your phone, not something that all people want or have. The signup process wasn’t even always available within the device, you might need access to a desktop to complete signup. They both require you to remember and accurately share an extra piece of info you have to memorize (email or username). They were both extremely slow, clunky and unreliable compared to WhatsApp.
Essentially, 95% of the reasons WhatsApp was successful were things you glossed over here.
That's not a replacement from SMS since those aren't based on phone numbers. If you have the phone number of somebody and they have WhatsApp installed you can message them immediately. If you both have AIM or MSN installed you have to exchange your handles through some other channel. That's a massive difference in terms of usability and friction to get started.
Could you chat with people on iOS with this? Or with people who didn't have a Google account, or didn't want to setup yet another account at all? Being a free and hassle-free drop-in replacement for SMS was the main appeal of WhatsApp at the time. If there would have been alternatives with the same features, WhatsApp would never have become popular in the first place.
Everyone (in Joel Spolsky meaning of everyone) already had an gmail account. Not giving out phone number was a feature.
When Whatsapp started out, it was free only for the first year; after that, they wanted a payment. What this experiment has shown, that people did very short term decision without regards for long term.
That's probably because you lived in a tech bubble already 10 years ago.
I reluctantly installed WhatsApp only after everybody around me started using it, or (the more tech savvy among them who already knew how to "open the internet"), switched away from Facebook to WhatsApp.
Everybody who had a phone also naturally had a phone number, and the phone numbers of their friends were already stored on the phone. Nobody outside the "nerd sphere" had a Gmail account 10 years ago, especially not outside the US.
PS: I don't remember ever paying money to WhatsApp, I think that was a short-lived experiment that didn't work out right before the Facebook acquisition.
It wasn't 11 years ago.