So yes, you can get the ICS for a single event, although it’s not consistent ([event] objects have both ICS and GCal options, [daterange] objects only do Gcal), but you can’t ICS a whole calendar (either from a topic or from a category)
I can chase CDCK about this, for sure. I’ve raised both that and the ability to filter/colour the calendar by tag/subcategory. Fedora and Ansible can see each other’s tickets, so we can ask their view too.
In short, I don’t think we can deprecate that link yet (nor should we, until we have critical mass here). However, I would suggest that as posts like Documentation Working Group Agenda are created, we update the ICS to link to them, so that people find the agenda for their groups. We should also make sure this goes on the new Project Onboarding doc @samccann is working on.