Free, no. Less expensive and more widely available than iOS devices, yes. Telegram also works on Linux, Windows and MacOS. There is a web version as well which works anywhere there is a reasonably recent browser available. The web version does not yet support calls as far as I know, this will most likely be added in the near future given that it is a rather trivial addition with plenty of free-software implementations available.
Only when you live in an Apple bubble which in practice comes down to the USA and parts of Europe. Elsewhere Apple is a margin player with the vast majority of mobile devices running Android. Telegram is available everywhere, for all "significant" devices and categories (desktop, mobile, web) which makes it a more universal option. It is growing at a rapid pace (200 million users in March 2018, 400 million users in April 2020, 500 million in January 2021 so probably around 600 million by now) with ~15% daily active users. This growth rate will probably increase with the recent brouhaha around Apple scanning devices in the hunt for illegal imagery.
For Telegram, your relying on the general populous caring that Apple is scanning their devices. I want this to be understood by the HN population: the general populous does not care about privacy concerns that they cannot see. They will not care that Apple is scanning for CP on their devices because they do not care that Apple scanned for Cp on the Cloud. The only time they would care is if Apple themselves were to physically send someone to their house, untie themselves in , and go through their stuff. Non tangible privacy violations outside of SSN data breaches are not on the mind of the general public.
There is also Nextcloud Talk [1] (based on Spreed [2]) for those who have their own Nextcloud server. I use both Telegram as well as NC Talk, quality is comparable. Telegram is a more capable messenger though, that part of NC Talk is underdeveloped.
I use both, and prefer facetime when I can (all people with iphones have it so barrier to entry is lower) - but Telegram is the next best thing for me.
