Well, we have legacy anyway, because I can't economically use TLS or DTLS this way, so I already have a proprietary protocol. Presumably other designers are in

Well, we have legacy anyway, because I can't economically use TLS or DTLS this way, so I already have a proprietary protocol. Presumably other designers are in the same position I am. And I'm not the only one looking hard at EDHOC and OSCORE, there are some pretty significant hitters in the IoT scene right now that are also looking at this and for the same reasons we are - standardized approaches in an industry sorely needing both standards and functional solutions that work on real networks. But yeah, building protocols is hard. I should know, since I've been building a dead-end protocol for over 10 years, including HSM support, massive scale, proxy scenarios, HA support, and blistering pen tests, that I am very ready to give up for OSCORE/EDHOC. TLS is not going to be "ameliorated by time"; RF isn't getting cleaner, radios are already very efficient, power management has gotten decent and there's not a lot left to squeeze. Putting bits in the air will continue to cost money. Embedded IoT will continue to chase the tiniest scrappiest cheapest hardware. Where do you think this "amelioration" is going to come from? TLS is going to get worse for IoT over time, not better. There will be ever more code points in TLS. The WG is going to continue to focus on big-box issues, privacy issues, server deployment issues, ever finer controls on timing attacks, extensions for SNI and other CDN issues. IoT problems will be solved elsewhere, with a different protocol, and that's fine.