I think what it comes down too here is that most developers are too cheap to pay for their own hosting and expect Github to provide free bandwidth and storage space for their compiled binaries and preconfigured projects. Github is a company at the end of the day and getting rid of the downloads API will probably save them a lot of money by kicking off the leeches who've been abusing and taking advantage of Github's storage and bandwidth generosity for far too long.
It literally costs cents for S3 and they offer a 1 year free usage tier for new signups. S3 or proper hosting is definitely the way to go.
For one it may amaze you, but some people actually pay for Github. Those same developers often have their own hosting (I personally have 3 linode vps's active for various projects)
The fact is it was just simpler as the maintainer of an Open Source project with numerous contributors to host it under one roof, all the contributors have their access granted in a single place, one set of keys to set up, one account to manage personally, and a single place to go look for X.
I am sure you love github and all, but I assure you you arent helping them by before anyone had even mentioned a word, insulting everyone who dared to voice an opposing opinion to this change, then continuing to do so in follow up comments.
It literally costs cents for S3 and they offer a 1 year free usage tier for new signups. S3 or proper hosting is definitely the way to go.