i once got 3 emeralds on OW last year.
(but a lot less this year)

in fact, these are spread over some 20 month period, due to different membership year starting points of these programs,
160k on AA for explt
2700 tier points on BA GOLD
and 65k to renew my CX MPO Diamond into Gold.

it is, in fact, not difficult to retain BA if you fly in th efront cabin,