I oppose. Mails are superior in announcing to multiple people. If people want to participate they can in many ways. It is well structured, well documented and offers coherent discourse. Slack/Teams are for just-in-time dynamic, collaborative conversation that are quickly fading and missing out on all the strengths mails have in terms of permanence, archival, search and general quality. Something that totally gets lost in instant messaging like Discord, Teams and such where context is basically non-existant and may be gone completely in minutes.
Remember Google+ ? What lasted was Gmail and barebone simple Mail.
Remember Google+ ? What lasted was Gmail and barebone simple Mail.