If you just want to apply the same workaround just for this form:
#show cite.where(form: "prose"): it => {
show regex("[A-Z]\. "): none
it
}
#let bib = ```yaml
a:
type: book
title: title
author: Doe, John
```.text
#cite(form: "prose", <a>)
@a
#bibliography(bytes(bib))
