True. There’s not a Christian church or group that is immune, either. That’s why pointing out the errors of this or that “Protestant” church is really no defense. Error is error, we’re provided with the standard against which it is to be tested. That’s true of any church of any kind and true of individuals as well. Will there be differing emphases? Sure. There’s room for that. There’s also room for disagreement upon meaning, outside the core, foundational message of salvation. There are many traditions and doctrines of many churches with which I might disagree, from mildly to strongly. Mild disagreements center around interpretation, not contradiction. Contradiction merits strong disagreement. That it sometimes comes from learned, even exalted men who wrap themselves in the cloak of infallibility makes it even more dangerous.
Yes, unfortunately, the Roman church teaches its members that it is infallible and cannot be questioned. The Roman church then becomes the measure of all things in a practical sense.
In some respect the church itself is worshipped, along with Mary and the saints.
Certainly, the magisterium decides WHAT scripture is, WHAT tradition is, WHAT the interpretation is. To say that the RCC is not above scripture or anything else rings a bit hollow when practice is observed.