Is Bitminter the last 2011-pool to shut down? Or are there any pools from 2011 still running?
2011 was a year a lot of Bitcoin pools started. Not sure how many it was, but it was quite a few.
2011 pools listed on
https://en.bitcoin.it/wiki/Comparison_of_mining_pools: Eligius (closed), P2Pool (still up?), BitMinter (closing July 1, 2020), BTCMP (closed)
I mined 2013-present first (and last!) on BitMinter, with lots in the middle on GHash (closed) and Eligius (closed).