> Permanent history
Slack frequently does not even offer this.
> embedded images and other media
Many IRC clients do offer this
> persistent notifications
I only get notifications when my client isn't logged in via Email. I can get this, and other options, with an IRC bouncer.
> additional software needed
There are web IRC clients.
> more intuitive access controls
About the same between Slack and IRC clients here. Click on a channel in the sidebar. Right click for more options. Type and hit return to send messages.
I use Slack, not IRC, but these aren't the real advantages for Slack over IRC.
Slack frequently does not even offer this.
> embedded images and other media
Many IRC clients do offer this
> persistent notifications
I only get notifications when my client isn't logged in via Email. I can get this, and other options, with an IRC bouncer.
> additional software needed
There are web IRC clients.
> more intuitive access controls
About the same between Slack and IRC clients here. Click on a channel in the sidebar. Right click for more options. Type and hit return to send messages.
I use Slack, not IRC, but these aren't the real advantages for Slack over IRC.