Unfortunately it seems difficult to discover how long they’ve been a member: https://news.ycombinator.com/item?id=24902985 They could theoretically have donated $2MM at $50K a year if they had joined back around the time when Bill Gates was railing about ‘theft’ of his BASIC (and others were replacing it with a superior ‘@copyleft all wrongs reserved’ one) ~45 year ago.

(Edit: of course cash is only one form of value.)