Your observations match mine. It doesn't bother me except for saving multiple prime seats, and I have never seen an FA challenge that. Not even spreading coats over 6 seats draws up front any reaction from them.

People advocating taking a "saved" seat overlook one aspect: Probably dozens of people boarding earlier passed up that seat. If the "saved" seat is to be occupied by someone else, shouldn't it be one of those earlier boarders? That would seem to be more fair. Or should the seat be considered compensation for taking on the job of open seating enforcer?