Perhaps its the filters being properly applied on the node runners using their filters (permitbaremultisig equals 0 datacarriersize equals 0) or perhaps the ordinals / inscriptions teams have lost their appetite or been persuaded for other reasons to scale back.
You cannot censor someone else's Bitcoin transactions from getting confirmed by miners no matter what filters you set on your own node.
The fee decrease is just the laws of supply and demand playing out in the long term. There's an infinite amount of block space being created, but the people who want to buy that block space have a limited amount of Bitcoins to buy it with.