That would be full circle. I remember back then when Jabber was popular, most competitors offered gateways (similar to the IRC-Slack gateway Slack closed recent

That would be full circle. I remember back then when Jabber was popular, most competitors offered gateways (similar to the IRC-Slack gateway Slack closed recently) so that people who used the popular open protocol would help spreading their closed variant. After a few years they would shut it down. But people never learn and I think the history would soon repeat itself.