In 4 years I have never (and will never) used any service from /e/. There is no vendor lock whatsoever. That’s fully optional.

Points 3, 4 and 5 in your list are moot IMHO.

Also

It takes a base level of understanding why you would buy a Fairphone

It doesn’t really. “Phone is repairable and X can help me”, “they pay the makers fair wages” are not really complex value propositions that require some (technical) understanding.

The point of /e/ and similar distributions is that you can buy a phone with it (average user will never reflash) and just have a phone that doesn’t use Google (it does, for the amount that doesn’t require you to do extra technical stuff and have a sane user experience at the same time).

That said, calyx seems a great alternative and so are iode. I think the advantages of one over the other (for my brief search) are quite small.