Well, religion sells, that much is clear. Who ever said that the younger generation were not religious? They are, they just changed their object of devotion.
Meanwhile my daughters use second-hand Android phones running AOSP-derived distributions, as do I myself. Only my wife - who has a company-issued Samsung Galaxy A40 which they do not want me to mess with - runs a stock distribution but I did manage to tame the beast by disabling snoopy Samsung "services" and installing an ad-blocking local VPN firewall. They haven't complained yet so I guess we're good to go.
For the price of a single second-hand iPhone SE2 (around $200 where I live (Sweden)) I could buy both my daughter's phones as well as my own. Still these Android devices offer far more useable features than that iPhone and they'll last longer as well if my 11 year old Motorola Defy which I use daily is anything to go by [1]. It still gets 3 days on a single charge, running the original battery - which is replaceable if so needed.
Instead of iMessage we use mostly Telegram plus some XMPP as a backup in case Telegram goes bad. My oldest daughter also has Whatsapp installed but hardly ever uses it. Our data is kept on the server-under-the-stairs, out of reach of greedy data hogs like Apple/Google/Microsoft/etc. The Invidious server (also under the stairs of course) keeps Youtube ad-free, our own mail server (under... you guessed it) keeps our mail from being harvested by data parasites, etc.
Just like iPhones often are stepping stones to largely Apple-dominated monocultures so these AOSP-derived Androids can be stepping stones to free software households. I do know which of these I prefer. There is only one system left here running Windows, this being my wife's company-issued laptop.
The moral of this post is that parents do have some influence over their children's choices if they start early enough. By the time they reach their early teens they are far more focused on what their friends do so make sure to inculcate a healthy distrust of Big Data and its marketing practices - green bubbles and all - in them. If it worked for us, it can work for you.
[1] The Defy was marketed as being 'IP67 waterproof and shockproof'. My oldest daughter used to have a Defy as well. She left it in her trouser pocket when she dumped those trousers in the washing and started the cycle. One complete cycle (at 40°C) plus 1200 RPM spin cycle later she found it - it was still working... The damage? I replaced the earpiece, for the rest it just worked. I'm using that device as a remote-controlled media player now. While rather underpowered and short on memory the thing still works fine as a "dangerous work" phone. You won't like browsing the Javascript-encumbred web on it though...