Did people of faith get it wrong until Martin Luther and his contemporaries picked up the pen?
It's not quite what Evangelicals would claim - as Evangelicalism is, allegedly, the best iteration/version of the faith - but the wholesale condemnation of Catholics seems curious to me.
There are a lot of people that think Catholics aren't Christian, so tell me, what are we to make of Christian history?
You mention Catholics, the Reformers, and Evangelicals. Orthodox are missing from your list.
I risk stepping on toes, but I will be as kind as possible and ask forgiveness from my Catholic and Protestant brothers and sisters in advance. We already know we have some disagreements with one another over doctrine.
Christ founded the Church. One Church. Of course, being made up of imperfect people, problems crept in. Errors of doctrine, pride, folks not getting along. We read of it in the Scriptures - it is nothing new. Thank God that He helps us and has patience with us.
Compared to today, there were relatively fewer departures in doctrine. Heretics did arise, but the Church pointed out their error, and there was a very high degree of agreement on doctrine and practice, compared to what we see today. Sometimes fierce disputes arose over what many Christians would see as a very minor point of doctrine, but the fact that they could be so mportant to them then serves to highlight the relative level of agreement.
Ok, fast forward. The Church was under the leadership of five cooperating and separate leaders. Rome was one of these five. Historically, the five were equal in authority, none of them ruling over the others, but Rome began to consider their position to have ultimate authority, which the other four rejected on the grounds that it had always been a shared responsibility.
Rome broke away, mostly over this, but some other issues as well, and the Catholics in communion with Rome was born as a separate body. The other four make up the body that persists today as the Orthodox Church (though with more leaders now because Christianity has spread to other nations).
Orthodoxy continues, basically, on its own timeline from there, with minor blips in relationships with other communions.
We believe divided authority and faithfulness to what was handed down from the Apostles maintains the Church essentially unchanged.
Rome now was a very influential body, under the guidance of a single Pope. Problem being, from our point of view, that means no protection from errors if the Pope introduces them. And from our point of view, Popes did. Such things as indulgences, purgatory, the Immaculate Conception, the Filioque, created grace, merits, Papal Infallibility, and ways of looking at sin (more juridical, division of venial and mortal, and related changes, along with guilt incurred through Original Sin, necessary temporal punishment of sin, etc.). Catholicism, from our point of view, changed greatly.
I think the Reformers were right to recognize that some errors were creeping into Catholicism. But honestly, they had lost the context the Church once had in order to interpret the faith. As a result, they made many good calls on what needed to be changed, but also made a few mistakes, because they were looking at Christianity already changed. In many ways though, the Reformers moved closer to Orthodoxy.
Evangelicals made further changes to the Reformers. The problem for them is that they had lost all of the early context. I do credit that their hearts were in the right place. And they often continue to be very steadfast and zealous.
The Catholics, meanwhile, to their credit have improved upon some of their earlier changes and moved back to a more historic understanding. However, I know many Catholics are not happy about reforms to the service itself, and they are not protected from progressive reforms if a pope decides to implement them.
What I don't quite understand is that Evangelicals are often taught a warped version of Catholicism, and then taught to oppose that version. I understand why they are opposed to some of the things they are told Catholics represent, but Catholics do not always believe what everyone thinks they believe? It's rather odd ... I suspect that misunderstandings and/or resentment contribute here and there.
I would just advise, if you want answers about a particular question, ask the ones who actually teach it. And also be aware that in most denominations or theological groupings, not everyone who subscribes to it will believe the same. If you get someone on the end of the spectrum of whatever belief, you can come away with a very wrong idea of what a denomination teaches.
And if this thread should become argumentative, you might like to ask other questions in Traditional Theology.
Hope that helps some, at least from our point of view. And please forgive me if I've offended anyone.