This is a performance point where general purpose Linux distributions ought to be competitive. The Debian project is really dropping the ball by not focusing a lot more on these use cases. Their debian-embedded working group used to lead worthwhile subprojects (known as EmDebian Grip/Crush/Baked) aimed at slimming down minimum requirements on all sorts of special-purpose hardware and even competing with the likes of Alpine and Void, but these have all gone nowhere. Hopefully they'll be picked up again since the mobile-phones use case is raising these same issues, albeit for other reasons.
Given that we have gone from two/three digit gigabyte disk to two/three digit terabyte disks, I'd say it held up pretty well ;)
100TB SSD, $40k.
[1]: https://www.friendlyarm.com/index.php?route=product/product&...
(2) It's interesting how much resources this requires now, though; 128MB RAM is recommended, and 64MB is barely sufficient. To fit into 32MB and run basic routing functionality, one needs to remove IPv6 from the custom configuration, for instance. Mere 15 years ago 16MB was almost plenty to run OpenWRT :)
I also wonder how much more compact a RAM footprint of a router can be if it only does routing, though competently: with IPv6, QoS, etc. Maybe it won't be much more compact even with a super-compact purpose-built kernel and network stack (not Linux).