Has there ever been a BIP to give a sort of priority value to transactions as a function of the passage of time : the more time passes, the more this value increases, which would, for example, make a tx at 1 sats/vB that has been waiting for 6 months a priority compared with a tx at 20 sats/vB that has been waiting for a few minutes.
Wouldn't (almost) everybody use very low fee because of that? and thus, wouldn't it lead to make a heavy mempool?