When VIP or Donator rank was made to be purchased, Bitcoin was far less valuable than today. It wasn't a negligible amount but back then somewhat affordable, if you think in fiat space.
I guess, nobody sane would buy VIP today. So what, who cares?
The last donator is
Claymore with passive income from mining software for Ethereum miners and miners of other altcoins in two cycles ago. Claymore left the forum since 2019 too.
Thanks to Claymore, the first Donator in quite some time.
theymos already commented on it: the set BTC price will not be adjusted to current fiat rates. It would be unfair to those who paid 50BTC, period. In your logic to demand to adjust the price for a VIP rank, would you also want to reimburse former VIPs for the difference of an adjustment? Think about it.
theymos said forum has enough money for operation and no longer need more donation in
BTC. Another reason shared by you is true, it's unfair for previous VIP, donator members if theymos decreases required
BTC in donation for getting these badges today.
In addition, it's Bitcoin forum and theymos does not want to receive donation in other cryptocurrencies. Exception is Grincoin in Copper membership member purchasing method some years ago.