SIP has some disadvantageslike a lack of NAT awareness, a common issue of SIP implementations while being fully compliant with the standard - cant interoperate,

SIP has some disadvantageslike a lack of NAT awareness, a common issue of SIP implementations while being fully compliant with the standard - cant interoperate, incompatible extensions, long call setup time, and a lack of defined minimum codecs. While I'm sure all of this will fix that, it becomes yet another protocol that will need to be supported - nor am I particularly convinced that encryption everywhere is something you always want (if I use SIP as an example, often packet captures are a hard requirement to troubleshoot why server A cant talk to server B). I'm open to it though, the TL;DR posted elsewhere in the comments is much more digestible than the draft standard. But it looks like it solves some of the issues with SIP, but introduces its own other issues.