Good for you, as a Linux user you can already download a version of the app optimised for your architecture (Intel/ARM). I'd like to see those options for the Mac app.
The point is not about the platform (Mac), or the disk size (cheap and plentiful), but about optimising distribution to save time (limited) and electricity (costly) on this planet.
Feature request:
https://bugs.launchpad.net/calibre/+bug/2017347