The bitcoin protocol allows miners to choose which transactions to include when they create a block. They can't include any inauthentic transactions, but to allow for an open market of transaction fees, they are allowed to choose which subset of authentic transactions they want to include. The assumption seems to be that miners are interested in maximizing their reward, and therefore would just include the subset of transactions that offer them the highest total transaction fees.
However, a miner with ulterior motivations might want to punish certain addresses. For example, a US government operated node might want to restrict transactions coming from an address that got its bitcoin through ransomware payments. As far as my understanding of the bitcoin protocol goes, it would be perfectly valid for them to never process any transactions from that address - no matter the price offered. With cooperation, they could greatly slow the speed of any transactions that had anything to do with that address. Of course, if there was even one node which didn't want to restrict the addresses activity, the transactions would eventually get through, but these neutral nodes might notice that that address has a harder time making transactions, so those neutral nodes might realize that they can demand a higher price for transactions from that address.
So the question is, would any of this be considered malicious activity?
Does the protocol consider a node doing this to be a "dishonest" node, from which blocks should be ignored (i.e. there is an explicit mechanism to prevent this kind of activity)? Or instead, are market forces (or some other implicit mechanism I'm not aware of) supposed to be enough to prevent this? Or as a last option, is this kind of behavior considered to be acceptable?
Edit: https://bitcoin.stackexchange.com/a/9412/124187 helped me understand this as well. The answer appears to be that this sort of censorship/discrimination is considered okay, and the capability to hashocratically discriminate means that the network can protect itself from things like market manipulation.