Did the Catholic Church really butcher 50 million bible-believers?

This claim has long ago been debunked by modern secular and religious scholars. Nevertheless, I continue to hear certain types of Christians repeat this number as if it is fact. So here's a bit of history on how the idea first came into existence. 

Three different men who all held bigoted views toward Catholicism first wrote about this in the 1830s. Charles Buck, W. C. Brownless, and John Dowling all wrote texts claiming that it had been "computed" that the Greek and Roman Catholic churches (these authors did not understand the differences between orthodoxy and Catholicism) were responsible for the deaths of at least fifty million true Christians. This anti-Catholic propaganda was further popularized by J. M. Carroll's book "The Trail of Blood", written in 1931. 

Carroll had no sources, but made an ambiguous appeal to history. He said, "as history seems positively to teach—then they died faster than an average of four million every one hundred years."

There are two main books written that went through Carroll's claims point by point to prove he had no sources nor ground to stand on. James Edward McGoldrick and W. Morgan Patterson not only proved that the claim of fifty million butchered Christians was false, it was also impossible. 

There was roughly 40-60 million people during this time period in Europe. If this claim were true, EVERYONE alive would have had to be a true Christian, and then somewhere to 60-80% of the population would have had to have been regularly killed and disposed of (getting rid of that many bodies would've also been impossible). These numbers exceed those of the Black Death. From records, we do know that there were atrocious acts of violence done by the Catholic Church, but even one of the most horrid instances we know of -- St. Bartholomew's Day Massacre -- only killed a couple thousand. Nowhere near millions. 

Those who continue to employ this sort of rhetoric prove that their bigotry for Catholicism outweighs their love of truth. Furthermore, in their attempt to pit themselves against Catholicism, they are willing to align themselves with heretics for the sake of clout. J. M. Carroll wrote: "Over 50,000,000 Christians died martyr deaths, mainly because of their rejection of these two errors [infant baptism and church-state union] during the period of the ‘dark ages’ alone—about twelve or thirteen centuries.”

And yet many of the churches he pointed to as true bible-believers practiced infant baptism and church-state government. The Lutherans, Waldensians, Donatists, Montanists, and Paulicians had nothing in common with one another or the churches who try to claim them as their own. It would be like a Baptist church pointing to a historical Jehovah's Witness church as proof for Baptist theology.

I have been sharing this information with anyone who makes these outdated claims, but there seems to be a psychological barrier. These types often claim to love truth and praise free speech. But they are unable to question their bigotry toward Catholicism. I'm not even saying one NEEDS to become Catholic, but if you're going to be anti-Catholic you need to at least get your facts straight.