this kind of thing could be mitigated by having transactions have a 1-6 block maturity after confirm. instead of using 'economics' to cost people out of utility.
not gonna help because they are not spamming with 1 address or with small amount of funds. they have always used hundreds of addresses (both when it was 10K satoshi with 10K fee and now as you can see in that address) and they have a large amount of funding. and a 1
BTC can be divided up to lots of small amounts. so they wait 1-6 or whatever number of blocks and then spend it and move to next batch.
6 conf is approximately an hour and it won't matter for the spammers but will screw users.