There were still internal costs related to running IRC though, assuming you weren't paying some provider to do it for you... not large internal costs, but I don't think on a radically different scale from Slack considering that you could also view a Slack subscription as covering a client with a lot more features than a typical IRC setup (sure you could run a web client, bouncers, services, but that's all increasing your internal costs).
I guess my point is that I feel like what GP refers to as "free" is actually just "developed/operated/maintained internally"... these commercial services are still by and large based on free software but you're paying someone else to do the work your internal IT capability used to do.
This couples with a general trend I've observed of organizations shifting their IT workload from inside to outside via PaaS/SaaS providers. This could be viewed as a form of outsourcing... in the '90s enterprises were moving their IT functions to India. Now they're moving them to a hundred different contractors, each supporting one system.
I'm not sure you grasp the absurdly low cost of running an IRC server even with the things you mention. You could probably support a nation-wide enterprise on a Raspberry Pi.
Bonus, unlike SaaS, you have complete control over the damned thing. New "features" won't suddenly get added to your tools that break your workflow, you can add new features if you need them without begging some vendor to whom you are a tiny insignificant nobody, etc.
Paying some provider to run a standard FLOSS service based on your needs is going to be a hell of a lot cheaper than some bespoke SaaS solution. And Matrix gives you those "rich client features" anyway, with a broad choice of client-side software - so it's a better comparison than IRC.
Indeed, Vector's managed Matrix service is quite a bit cheaper than Slack. but it's also effectively subsidized by Matrix's patreon backers, such as myself. Not necessarily saying this is right or wrong, just that the money always comes from somewhere.
Additionally, as a rather dedicated Matrix user and advocate, it's clearly less stable and usable than Slack at present. See e.g. the effort towards a complete rewrite of the Riot on mobile and significant changes to Riot on web. Most third-party clients are not feature complete and are often rather unstable themselves (e.g. I am a heavy user of the Weechat python plugin but it takes expertise to get it up and running). The pricing no doubt accommodates the fact that anyone adopting Matrix for business use is going out on a limb to some extent.
> but it's also effectively subsidized by Matrix's patreon backers, such as myself.
I think that's the wrong way of putting it, since that Patreon money is clearly paying for the open component of Matrix. That's work that needs to be done anyway, whether Slack exists or not, and whether businesses choose to host their service instances via Vector or not. And it's definitely a Good Thing that FLOSS suppliers can now get funded via those crowd-based mechanisms - both for aligning incentives and for enhancing the overall "community"/"bazaar" aspect that has helped make a lot of FLOSS software successful in the past.
I guess my point is that I feel like what GP refers to as "free" is actually just "developed/operated/maintained internally"... these commercial services are still by and large based on free software but you're paying someone else to do the work your internal IT capability used to do.
This couples with a general trend I've observed of organizations shifting their IT workload from inside to outside via PaaS/SaaS providers. This could be viewed as a form of outsourcing... in the '90s enterprises were moving their IT functions to India. Now they're moving them to a hundred different contractors, each supporting one system.