I don't think it is. The first comment (the one you're referring to I suppose) just doesn't make any sense. The commenter is throwing around random buzzwords trying to sound educated and asking incredibly stupid questions on purpose. It's not fair criticism of the project at all. The secureblue account also replied to this, clarifying the misinformation from the first comment.
Well at some point you do need to buy a phone. Pixel devices are excellent, because they offer a minimum of 7 years of updates. With the legacy extended support on GrapheneOS you can get close to 10 years of lifetime out of a device, while retaining security and privacy.
What do you mean?
You can always get a used or refurbished device. It's good for your wallet and for the planet.
And make sure to get a used or refurbished Pixel, because giving Google money isn't a good idea either https://reddthat.com/post/32690381
Not a real replacement for AirDrop, since it still requires devices to be on the same network, instead of using ad-hoc Wi-Fi, but LocalSend is pretty nice.
Which features of Time Machine do you need? Just backing up, or do you also need the file history?
For backups the best solution we have is probably Pika Backup (it uses Borg Backup under the hood, so it's compatible with other tools that use the same standard). There's a pretty good video about it: https://www.youtube.com/watch?v=W30wzKVwCHo
It also lets you grab individual files from a backup, but it doesn't look as nice as the Time Machine file history UI.
It'll cost OpenAI a lot of money.
Or you can always grab a torrent: https://meta.wikimedia.org/wiki/Data_dump_torrents
Also make sure to seed, preferably on a dedicated machine with an unmetered connection and high bandwidth.
Is that just the English version or all languages?