You are right that IP checks are lightweight, though you miss that setting up TCP/IP handshakes is algorithm-heavy, but it’s transparent because hardware and ke

You are right that IP checks are lightweight, though you miss that setting up TCP/IP handshakes is algorithm-heavy, but it’s transparent because hardware and kernel optimizations keep it light on the CPU. TLS encryption, through certificate checks, key exchanges, that whole negotiation, is a CPU-heavy activity, especially on servers. Most of that asymmetric crypto, like verifying certificates, isn’t helped much by hardware accelerators like AES-NI, which mainly help with session encryption. TLS is already tons of work, so HTTP Message Signatures and mTLS are like piling more hay on the stack, it’s extra work, but you’re already doing a lot at that point. The real complaint should be about having to adopt another standard, and whether they’ll discriminate against applications like legacy RSS readers, since they’re considered a type of bot.