I think the "clogged follicles" causes hair loss thing is the latest bunch of nonsense from hair product sellers. So far as I am aware, there is no evidence at all that follicles can get clogged enough (in normal life) to discourage hair regrowth.
They chain of circumstances would have to be
There is something in facewash (which one?) that stimulates sebum production - doubt it, that would negate what facewash is for.
The something in facewash that I don't think exists is capable of travelling around from your face to your scalp
The something in facewash then capable of stimulating sebum production in hair follicles which again I doubt given that it shouldn't be stimulating sebum production anywhere as that would negate its purpose (are we bored yet?)
The overproduced sebum is capable of clogging hair follicles
Hairs are prevented from growing by having their follicles clogged with sebum.
Never say never but it looks pretty unlikely