I myself have been a happy user since when my daily driver phone had a 320x480px screen, 512MB RAM, and ran CyanogenMod with some alien skaterboi mascot ;)
I consider helping my family with their tech stuff a privilege, not a burden. They help me with so much, why wouldn't I want to guide and support them on things I am knowledgeable about?!
I'm not sure why the author thinks Lineage is easy enough for a non-tech savvy person to install...I mean, if you've got this guy to do it for you then you're good I guess.
You can have multiple profiles in Android, so you can, for example, have your main GrapheneOS profile be google-free and have a "spyware trash" profile for things that won't work without tithing to Sauron.
Graphene is only supported on Pixel devices however.
as long as he'll also provide the bimonthly necessary tech support with a fast response time.
Personally, I would aim a little higher though. I run it on a Pixel 4a and am quite happy. (Don't get the Pixel 4/XL since those do not have a fingerprint reader but only Face Unlock, which the latest LineageOS does not support.)
Unlocking the phone's bootloader is also not so easy, because you have to register your phone online and the web page is quite finicky. I had to try with different browsers to get the registration form to work.
Previously I had a Moto One Action and the system had a few quirks, but overall was OK.
I remember that ages ago I had to use Magisk and a finnicky Xposed module on my phone to be able to get past the root protection my banking app had. I'll be honest, these days I just don't have the mental energy for those sorts of fights anymore.
Same, funny how we're basically putting "rootkits" on our phones. At the end I also gave up having root on my phone, because it seems the banking app(s) were too clever and detected them.
I've never rooted mine, running LineageOS since 2016 + minimal Google services. There was a period when my bank's app suddenly decided things weren't "safe" and refused to run but this was many years ago - no issues since.
That should cover at least the notification side. If I can't bank on a mostly open-source mobile OS than I would rather just not bank on mobile at all. Banking on stock ROM is not an option for me.
Also, there is nothing stopping you from just keeping an old phone around just for the banking app. It's not like I really need to do banking on the go, and the app is nothing more than a glorified 2FA app for when I do home banking, on my actual computer.
On my phone, using crDroid (no official lineageos support), I can use Google Pay without problems. This wasn't possible when it was still rooted, so I think root access is what prevented that from working before.
As for Google Play, you can just install those right after installing Lineage. Or you use MicroG or something if you don't like the closed source Google services client.
If there are any banking apps that run on LineageOS, kudos to them - if they are available in Germany, tell me so I can switch...
having said that i love anything anti-google but i'd be careful to advertise it to others.
It's kinda funny that device integrity is so important to them, implying evil maid attacks, but the most common attack on eID is simply stealing someone's code or convincing them to use their eID over the phone.
Of course, with the evil maid attack enabled stealing someone's phone would become much more common, rather like stealing someone's credit card.
I ended up with 2 phones because of that and my second is an iPhone mini, because of the shitty financial apps that didn't work properly on Android. The upside of a walled garden I suppose is that the bank would test it properly on a more consistent iOS.