> There is a long-established tradition that formal scientific writing should avoid use of first-person pronouns in general because it makes findings sound more subjective. It's taught this way from early on.

Established tradition doesn't negate "collective delusion".

And anyone who uses the use of "I" in a paper to imply anything about its authenticity is definitely indulging in some form of a delusion. It's not the norm, but is definitely permitted in most technical fields. When I was in academia no reputable journal editor would take seriously reviewer feedback that complains about the use of I.