1. Spare emails, like, lots of them
2. Users of mail.ru and such are their own worst enemy, and it's not like getting gmail address is particularly difficult
Last time I checked I couldn't create a new gmail account without a new phone number.
Anyway, emails these days are nearly instantaneous too, not that much slower than, say, WhatsApp
it's sad, but it's like this.
Also Telegram is deeply integrated into Russian infrastructure. Fair amount of the private companies use it as the main communication medium. Government entities use it to communicate the news. Lots of common non-political folks use it.
I would bet trade-off of upsetting non-relevant folks to the hit of the unfavorable party doesn't really pay off. Apple and Google may move their employees after these events.
I'd argue both apple and google are well-integrated too. A lot of businesses and people depend on them and sometimes in very unexpected places. For example, apparently yandex's own smart speaker uses 8.8.8.8 to test internet connectivity. A lot of services use recaptcha too.
It wasn't removed at the time, and all sources that Apple and Google were demanded to block it in Russia pointed to press-release on RosKomNadzor itself.
I suspect that it is possible that all this Telegram block in Russia was a PR campaign coordinated with Russian government to give Telegram a reputation of a messenger that doesn't abide to tyrannical governments.