I think I have to disagree with you here! The consensus is reached when the majority of a group agrees to something or to do something. The 100 policy is a consensus in this case and no longer a policy because we all know that the majority of node operators will not change this setting. If the majority of nodes agree to something then this becomes a consensus, not a policy or a default setting.
Consensus rules are the rules that must be obeyed, so that the transaction or the block is valid and accepted by other nodes.
For example, one of consensus rules is that the the total value of inputs must be equal or greater than total value of outputs.
If a miner includes a transaction in which the total value of outputs is bigger than the total value of inputs, the block would be rejected by nodes, because it doesn't follow consensus rules.
Some rules are usually followed by nodes and miners, but it's not that miners and nodes have to follow them. These rules are called standard rules.
For example, almost all nodes would reject any transaction with the fee rate of less than 1 sat/vbyte, but miners are free to include a transaction with zero fee.
BIP125 isn't a consensus rule.
Assume that I have broadcasted a transaction paying 50 sat/vbyte and that's still unconfirmed.
If I broadcast a new transaction with the same input(s) paying 1 sat/vbyte, almost all nodes will reject the new transaction, but there's nothing that stop a miner from including the second transaction and a block including the second transaction would be valid.
What I said in my previous post is a policy that is followed by almost all nodes. That's standard rule, not a consensus rule.
Assume that I have made 110 transactions and they are all unconfirmed. Now I want to make a new transaction that would invalidate all those 110 transaction. Almost all nodes will reject my trasnaction, because it doesn't follow BIP125 rules.
What will happen if a miner include my new transaction? Would the block including that transaction be valid? Yes, the miner wouldn't break consensus rules and the block would be valid.