A lot of them run BSD, not linux, which wasn't affected
That would be a bold claim and one I've never heard before. Hard not to be suspicious of it.
This security flaw is unlikely to be the only security flaw that ever happens to a kernel used by routers.
The point: Consumer routers do not seem to get updates. Ever.
Is that a worry or what?
But what do I know about it beyond that?
Some more commercial ones (pfsense is commercial) use it too like juniper junos.
Any router/switch is going to be running an ancient Linux kernel, which isn't patched. EdgeOS for example, won't be patched. The old Brocade/Ruckus switches I got here, won't have this patched. I'm holding my breath for my Unifi APs.
Of course it does. But it was not affected in this particular case.