I wish All Metal and Duraglass would just go away. It is the hack answer to everything. Filler is fine when used correctly. You need a good quality filler like Rage Gold, Rage Extreme, etc, not cheap crap. Old fillers had poor corrosion protection, which gave fillers a bad name. Everybody thinks duraglass is water proof, so it should be used. Every car I worked on that had duralass in it had rust starting under it. All metal is a joke too. These products are still being sold to back yard hacks that think they can fill a rust hole with them. Fillers are made to fix dents, not holes. It shouldn't be thicker than 1/4". If more than that is needed, then the panel isn't ready for filler. Back to the metal work.
The next step, etch primer. A spray can etch primer is not designed to be used over large areas of bare metal, just small break throughs. Epoxy is about as outdated as Lacquer. I would use it on a frame, floorpan, or underhood, but not on an exterior finish where gloss holdout is a concern. An acid etch should be used. Your finished product is only as good as the products used. And the products need to be used properly. There is alot of misinformation when it comes to painting. People misuse products and blame it on the product. The worst part is one bad job by a hack gives the entire industry a bad name. But what do I know?
