I see mentions of Screen Hero in a way that makes it sound like it's dead, but my team still uses SH daily (via Slack's `/hero` command). It's easily the best _remote pairing_ tool that I've found. This new Slack feature seems like something different, for presenting content to everyone on a call, not for collaborating on code.
On https://screenhero.com/login they even say "New signups are closed while we integrate with Slack." - I consider that "dead."