These responses are actually proof of the apostasy and not a protection against it.
Virtually all false doctrines in the history of the church have been taught by "the clergy." Fact is, most clergymen in the churches don't know the true gospel of salvation in Jesus Christ.
But your pastor knows the true gospel, right? Well, I know many that do. And this distinguishes them not at all from the believers in their churches. Believers can preach the gospel and are commanded to do so. Preaching the gospel is not reserved for a small subset of believers, it is commanded of all. Need I cite verses?
But you say not all are able to teach. No, not all. Not many are teachers, but many are able to teach. There is a difference between being able to teach and being a teacher. Elders are to be able to teach. Not all of them are teachers. Likely most of them are not. But they are surely able to teach. In the same way myriad millions of Christian men are able to teach in the churches without being teachers.
Does one need to be a teacher in order to defend sound doctrine in the churches? No, not at all. Otherwise how can any of us withstand Satan's arrows? If you grow up in Christ you can defend sound doctrine; if you have not grown up in Christ you cannot defend sound doctrine. I am speaking of Christian maturity or perfection. I say again, for the thousandth time, Christian perfection is maturity and not sinlessness. It is another proof of the apostasy that I must defend myself when asserting the doctrine of Christian perfection. It isn't taught in your churches, is it? No, never, otherwise you would grow up to reject the clergy system that never teaches Christian perfection. (John Wesley's "A Plain Account of Christian Perfection" made a miserable mess of the doctrine, and it is still considered a Christian classic by legions, today.)
When Christian men and women leave the churches-in-buildings to meet in houses, they run up against false doctrine and the problem of how to deal with it. The problem is they were never built up in their church-in-a-building so that they could contend for the faith. They were never perfected, the very word contained in Ephesians 4:13, where it unequivocally indicates that Christ gave His gifted men to the church in order that they should grow up to maturity. When? When we get to heaven? No! Now!
When you grow up you don't need a teacher any more. Except you need the Teacher, that is, the Holy Spirit. You do not stop learning, and yet you have been schooled in the fundamentals of the faith, haven't you? You still need teaching, but it is more and more direct from the Word and without the explanation (exposition) of a human teacher. You may read Christian books, too. But what you don't need is the Word expounded to you Sunday after Sunday ad infinitum in which case the men's speaking gifts are never exercised in the primary meeting of the church, and thus these gifts atrophy.
The sermon system, by contrast, is predicated on the idea that the people never grow up and never can grow up, but they must be continually through the decades of their lives be ministered to in order to maintain--what?--their childlike state in Christ. They are mere babes in Christ!
In the secular world, babies grow up. But not in the church! Not in the spiritual realm!
Romans 12:3-8 does, indeed, "work." But it only works when we walk by faith and not by sight.
The fact that so many Christian men and women find it very difficult to contend for the faith once they begin meeting in houses is proof they did the right thing by leaving their old churches. They need to stay the course and start growing in the faith. It is not as easy as simply "going to church." The road is fraught with peril, just like a pilgrim's progress is.