...once upon a time. My sense of it is that there are WAYYYY more than 100 collectors with 500-520 T206 cards in their collection. I'd say closer to 500 people have that many. Perhaps even more.
Seriously, there are so many T206 cards out there -- I mean, just check ebay and compare the number of listings with any other baseball card set in history. Most of them are just so common.
I think a lot of people get into T206, as I did, because the cards are 100 years old and they are also somewhat plentiful and affordable.
I still really love T206, but having immersed myself in autographed pre-war cards, it's hard to spend any real money on an unautographed Larry Doyle card when none will ever surpass this one: