I dont think any of us said filas dont work anymore, what i think your trying to say is that only cafib filas are working dogs. I dont think you were around when i had my farm and sent in numerous pics of my cbkc filas working my livestock, hogs, cattle, sheep and goats and many many ducks and chickens, my one fila also only had 3 legs and he was my best stock dog lol. These were city raised filas before we moved to the farm and they had no issues of attacking the animals, they were so easy to train and never had any worries about them hurting one of my animals. They also helped me locate my free range egg layers nests in the long grass, their reward was an egg so they liked playing that game lol. I got to see alot of natural instinct come out in my filas when we moved to the farm, was there for 8 years so got to experience alot with my dogs. Also back then there were alot of fila owners in the US that did participate in the livestock herding instinct tests, i do believe Suzy took her filas, cbkc filas and her dogs preformed quite well, as well as other cbkc filas, that you consider to be mutts, they also passed there temperament tests as well with flying colors.
Also when you were stating about the looks of the fila, no where in either standard does it call for a long ear, i do believe it says large thick and v shaped, inset at eye level and to the rear of the head. The old black and white pics i have seen of filas do not show long houndy ears as the cafib dogs of today have. It seems like every year the ears get longer and the head narrower, in my opinion they are losing the molossoid look to them.