Most are sadly destroyed by Satan's attacks and if we look at the largest denominations within these, they are already pagan -- the ECUSA leading the pack (and the CoE not far behind) with the ELCA, PCUSA following
Newer groups such as Baptists, Evangelicals, Pentecostals are break-aways from the first so are not technically Protestant as they did not break away from orthodoxy
They are also varyingly different in theology and beliefs from orthodoxy -- some close, some extremely far (for example the Oneness Pentecostals reject the Trinity, a basic Christian belief and the Seventh Day Adventists have concepts as strange as "Satan taking on the sins of the world" etc.)
Your post is a refreshing observation. The term "Protestant" has always contained the root of rebellion anyway; but it was a sharp cultural distinction during my long-ago youth. I have identified as "evangelical" since leaving the UMC ten years ago, and have subsisted primarily on house churches centered on prayer.
Currently I am commuting 130 miles roundtrip once a week to go to a class on the schism at a small Lutheran church where the pastor, age 30, is a committed Bible-believing purist and social conservative. That alone is a cultural phenomenon worth the gasoline; and the class is excellent as well. A small group of Christians in a small, musty basement of a tiny church out in the mountains, studying the Lutheran reformation, Luther's small catechism, the Creeds and so on.
Like old times, but for the lions (so far).