Nesting limit. Replying to:

I suspect a secret handshake was made to switch off permanently or temporarily, it is a free service at the end of the day so i'm thankful for it

I agree. Seems consistent with "the whale experiment."

FYI, if the others go away too, you can get most of the block chain information by setting up your own low memory node in a linux vm with 4g of RAM (and a good bit of disk space). The only thing I've noticed (so far) that's missing from mine are the secondary tags.