"The Church isn't one group or another. It's everybody who has faith in Jesus.
This is not correct. The Church is One, Holy, Catholic, and Apostolic. Only the Holy Roman Catholic Church completely fulfills this definition. While I accept that there is a possibility that there could be people who have true faith in Jesus and who may achieve salvation (i.e., Baptism of Desire according to the mind of the Church), though this group is exceedingly small, they are not actually incorporated into the Church unless, through miraculous means, they find themselves members of the Church Suffering.
There's no perfect Church because there's no perfect people.
A non-perfect Church would not be Holy. Of course there is a perfect Church. The problem we face today is that an apostate sect has co-opted the name of that perfect Church and stolen its property.
Even if the Church used to all have the same teachings, people are sinners and they went into error and the Reformation changed that.
The first part is a given. The Church continues to have the same teachings as it has always had. People are indeed sinners and have gone into error. The so-called Reformation, really the Revolution, only changed the errors and multiplied them each sect splitting over increasingly fractured errors.
There's errors in the other churches, too, but that doesn't mean they're all wrong.
This is just plain silly-talk. Error is, by its very definition, wrong. Every sect, be it Protestant, Jєωιѕн, Islamic, Hindu, Wiccan, Buddhist, Sikh, Orthodox, Conciliar catholic, etc., etc., etc., is founded upon error and is, therefore, wrong in at least one critical doctrine of the faith.
It would be impossible to truly have a discussion with anyone who makes the final statement because that individual simply will not accept the self-evident truth that error is, by its nature, wrong.