Not at all, perhaps only a modicum of technology confidence to do the install, though I can understand how it can feel/seem a tad daunting. Sent from my GrapheneOS pixel with no sysadmin knowledge 🫡.

I don't think it was ever that troublesome. But custom rom support was indeed a hit or miss thing. I bought FP6 with /e/OS preinstalled for this reason and had no issues. At least no major ones. No babysitting required stuff just works.

Other popular option is google pixel with graphene.

Only if you consider using a different app than the play store to be sysadmin, really. Depending on your reliance on proprietary apps and ability to accept foss apps, it doesn't have to be much different.

Using GrapheneOS is as simple or as complicated as you want it to be. I'm not de googled entirely as I use the play store for some apps, but running the sandboxed play store and an F droid client is all it takes. That's like 5 minutes of setup. It's really not different from stock android or iOS except I have two app stores to choose from instead of one. It all updates automatically and just works