I've had mortise & tenon plus pocket screw from the factory fail on chairs. Granted they were probably 20+ year chairs. I'm very weary of pocket screw alone as the materials don't warp and bend the same way. I've built a couch using wedged tenon (mostly just for fun), that spent many years outside without major issues. I've made indoor, load bearing furniture, with just glued dowels fail after maybe 4 years indoors. The glue failed in this case, and I think I used Gorilla Wood Glue. IDK, if you want long lasting stuff, I've came to the conclusion that most of the load needs to be bore by the the actual wood joinery, and glue just to keep it in place.