Looks like Discord notifications are the preferred method by most people on Twitch to receive reliable notifications with additional useful information. (Twitch definitely does not do this.)
Discord also has a rich API for building this out custom in a way that
allows me to map my iam modes with a specific role so that people can
give themselves the role and then be notified only about those mode
notifications. The bonus is that people in the Discord chat will be able
to identify each other’s mode interests in the channel in addition to
just meeting each other in the community.
This is one of those times when Discord outshines plain IRC. People can put Discord on their phones and will receive a very specific notification if they wish. There’s just no better way that appeals to the largest audience for setting up this kind of stuff.