Why do some 2000 elos not have diamond membership?

In before the posts about the benefits of being a free member.

I don't think your rating if high merits anyone paying for diamond membership, its surely down to whether one can afford it, I am currently a paid member but sadly won't be when it runs out due to having to retire due to health reasons so won't be renewing its down to costs so will be continuing as none member but rarely play more than 8 games at time and only at 3 days per move.
that just sound like pay to win for me

I don't take chess seriously - I just enjoy it as a hobby.
Also, having a membership won't guarantee that someone reaches a titled level of play. That depends entirely on the player.