What? Knots is only different from Core with regards to some features like mempool policies. Nothing that you could not add in your Core config file, by the way. Mempool policy is not "protocol rules", is stuff that you are willing to relay, given that you do not break protocol rules. If I decide that my node does not relay any transaction at all to the network, there is nobody stopping me. Moreover, I'm not breaking protocol rules.

What's the point?