In reply to both:

Yes. I agree. Messages sucks.

But most of the team is nontechnical, and don’t want to use Slack. I am not in a position to insist otherwise.

Messages works OK for most quick conversations, but is no good for anything of technical substance.

So I am keeping my options open for alternative mediums that the team will actually use.

Yeah what? I use macs a lot but Messages is abject garbage and isn't even a serious competitor to Teams/Slack/Discord. It's meant for texting but on your computer...