Earlier quoted context omitted.
"Ubuntu and Debian" "average user" I dont disagree with your point, not sure it is relevant however.
The pretense that all Linux users should be (or already are) technically capable is really harmful to the ecosystem. No, you should not expect Ubuntu or Debian users to figure out on their own (1) why the tar.gz file they download doesn't do anything meaningful and (2) how they will get this version of Firefox instead without any further instructions. Running Firefox from a tarball is a very specific use case for a s…
If someone knows what Debian is and has chosen to install it I think its fairly safe to assume they have some Linux knowledge.
Ubuntu on the other hand is the most likely to work without any tweaking. Its the default choice for less technical people wanting to try Linux as well as more experienced people who want a hassle free install.