If your first paragraph is correct, and I have no reason to doubt it, then there is a large and rather unobserved discrepancy between content creators and the run-of-the-mill commenter who likes, upvotes, comments, etc. but does not upload. I suppose then that the philosophers are more interested in becoming 'public faces' or 'public intellectuals' than the scientists and others. It's a tough one: I usually think of philosophers as tending towards introversion, but our version of them conversely tend to be very talkative. I suppose it isn't impossible. Many of the Ancient Greek philosophers, often living in communes with the like-minded and writing very little (or nothing in the case of Socrates, who was averse to writing), clearly would have talked more than they wrote.