It matters when you have to download the file over a slow network.
"The ideal size is 10-15MB globally. Idea size for an app for tier 2/3 countries (like India) is below 5MB. 500MB+ is a non-starter. At 50MB+ the conversion rates fall off dramatically."
Go binaries compress well in my experience. For example, I have a Go program that compiles to an 8.2 MB binary when compiled with gc 1.4.1. With bz2 compression, which takes about half a second on my box, it can be shrunk down to 2 MB.
"The ideal size is 10-15MB globally. Idea size for an app for tier 2/3 countries (like India) is below 5MB. 500MB+ is a non-starter. At 50MB+ the conversion rates fall off dramatically."
http://time.com/3589909/internet-next-billion-mobile/