See, for me, although neither choice is ideal in regards to actual congregational singing, if given only those two choices, I would definitely go with the trained musicians over a folk mass any day and would rather participate and pray by listening to their God-given gifts than to have to sit through the other and try to find something nice about the folk-like music. Although, since I am a trained musician, I’d be right there in the congregation joining in with the trained musicians.
I think we have to be careful about using terms like “love to show off their talents” with most musicians or singers/instrumental players who give of their talents for mass. That kind of wording can come off as very negative, even if it is not meant to sound that way. (I’m not saying that I felt you were meaning for that to be negative, but I’ve seen many comments like that which were taken in the most negative connotation by others.) As a musician, it’s already hard enough dealing with people who assume things like that just because you are a trained musician. No need to add fuel to their fire.
Many musicians I know, whether in the church world or secular world, don’t “love to show off their talents”. They humbly realize it is a gift from God or whoever they believe in, which can be easily taken away from them. Many want to give of themselves as prayer and as a servant, and there are many, like me, who beat themselves up all day long if they screw up even one little note because they believe in giving their utmost best for God and to those who are listening.
This is for any kind of musician or those who can’t read music, but do sing or play an instrument by rote. Of course, there are always show-offs in any field, but I don’t think they are as much as in the majority as some would think. We really can’t know what any of those musicians are thinking unless they tell you themselves or you talk to them and realize that they are doing it more for their glory rather than for God’s.