I understand what you are saying directionally, but there are a few breaks in logic here: Filters do work, or else people wouldn't be so upset that some people use them. Using a filter is a market action, all human action is. I would submit that it is about OP_RETURN because it was the first placation to spam and arbitrary data that caused this escalation. Prior to making op return a standard transaction within certain byte parameters, it simply was not propagated to other nodes when an op return transaction was found. OP_RETURN was given to spammers as the less bad option, but I completely disagree. Eventually, the UTXO set will be "bloated" anyway, from use and the increased value of Bitcoin as money. Let spammers use fake keys to compete with monetary transactions. I see that as perfectly fine.