You wrote:
“I think they would beg to differ!”
Not a single one of them would beg to differ if given the chance. Not one. No one in the entire period before the rise of Protestantism would have claimed to have been a Protestant since no such concept existed. People do not claim to be members of movements that have never yet existed. Sorry, what you are proposing is logically impossible. Anachronism of the sort you are suggesting is completely illogical.
“Many tried to reform the RC church from within at first, which I think is the right thing to do. Some succeeded. During the Reformation, a mass split occurred.”
No. If some Protestants succeeded at what you call “reform” in side the Catholic Church, then there would have been no need for further “reform” on the part of the Reformers, nor would there be a Catholic Church today. Again, what you are proposing is logically impossible.
“No one in the entire period before the rise of Protestantism would have claimed to have been a Protestant since no such concept existed.”
Quite so, I don’t think the word “Protestantism” would have been used. Yet there were many reformers over the years, who protested heresies in the RC church, some successfully, some not so.