Having the option of native clients, whether on desktop or mobile, is good. Having a mobile app that fully respects its platform's design language or a desktop client that uses less resources than a web browser and will run without issue on something like a Pi can go a long way to making a web platform enjoyable to use.
Hell, you could tweet from a BBS at one point (maybe you still can?) and until July 1st you can browse Reddit in a Linux terminal using basically zero resources. Lemmy has this neat project for a web interface that will run on a toaster, for example. Maybe kbin will get something similar once its API is mature.