I don't think many chemists want to admit that there's very little reason to believe any PFAS formulation could ever really be safe. Perhaps one could be designed to break down faster and be less bioaccumulating in animals but realistically their mechanism of action as surfactants - the reason they're so industrially useful - is the very reason they're toxic to living organisms.

Surfactants fundamentally change the surface tension of water and other fluids which has an effect on everything from how biological surfaces adhere to each other (including to the internal extracellular matrix that most multicellular life depends on to organize its cells) to how proteins fold together. Normally surfactants like soap, lecithin in egg yolks, and glycolipids are not a problem because they're immediately biodegradable but not PFAS.

The carbon-flourine bonds that make them so resistant to breakdown and so bioaccumulating are the reason why they work in such a wide range of industrial environments, surviving high temperature and strong redox reagents that would normally rip apart any other molecule. It's the worst kind of catch 22. The whole class should be banned and the industry forced to live with the consequences like all the anti-fouling agents that are banned in the maritime industry.