Hey Morgana,
Seems like you are overly obsesessed with the Protestant side of the issue?
Maybe just a tad bit (Catholic) self-defensive?
The term “Protestant” has been stretched to be practically meaningless.
Right now we use it as a catch-all for “Western non-Catholic groups who vaguely say they are Christian”
Note that I said “vaguely” - because we have
1. The Oneness Pentecostals who deny the Trinity - are they Christian? They say they are
2. The Unitarians - who were and called themselves Christians until the 1960s, now they don’t
3. The Christian Scientists
4. The Seventh Day Adventists.
And the myriad fundamental differences between the different groups labelled “Protestant” - like Lutherans and Anglicans having an episcopacy and having sacraments (the Lutherans consider the Eucharist to be the True Presence of the Body and Blood of Christ) v/s Baptist beliefs of the same. etc. etc.
We need to come up with another term — I use the phrase “Western non-Catholic groups” — or WeNoCgos