I have noticed this as well. I usually check 5/6 specific searches daily or every other day. "Vintage Campagnolo" is one, and I look Worldwide; there are times where there are less than two pages (100 items) of stuff listed, and it used to be double that at least - and most of it seems to be from online retailers, not private sellers.

I mainly look to keep abreast of values, on the off-chance I will see something I need/would like to have for the future. I get a good idea of value, and how high I'd be willing to go by reviewing Sold Items using my search terms. Prices seem to be coming down along with the lack of stuff.

DD