clarry: For sure. Hosting isn't free, and there is no way a company could be mandated to host some piece entertainment and offer downloads for all eternity.
AstralWanderer: Using a Content Delivery Network (CDN) makes bandwidth costs negligible (see
this Backblaze blog entry for some cost examples, like Amazon Web Services starting at $0.085/GB). Even if you only purchased content at a 80-90% discount, you'd have to do a lot of downloading to come anywhere near the cost of the game in question.
You don't realize how outrageously expensive that is? That backblaze article ends with "we think the world needs lower egress fees" and I fully agree.
At 0.085/GB, a game that takes a few tens of gigabytes would cost a few dollars to transfer. Now take a game like Wolfenstein: The New Order and assume GOG's cut from the 20 eur asking price is the industry standard 30% or 6 eur. That's already in the "few dollars" range, and I believe that price includes VAT. That's bad even before any kind of discount!
Now I'm pretty sure GOG is large enough to negotiate *much* lower bandwidth fees, but for smaller companies, these fees are high and cloud providers like to keep their clients hostage with high egress fees, ensuring the client does everything to keep as much of their traffic inside the same cloud provider's network -- paying out of the nose for services that could otherwise be had elsewhere cheaper.
You don't get a CDN because it's so cheap, you get one because it's an easy way to offer fast downloads worldwide without requiring you to maintain your own scalable infrastructure for that. If you look at what (traditional, non-cloud) hosting providers and data centers charge for egress, you can get much cheaper bandwidth than any CDN publicly offers.
I'll add that data transfer isn't the only cost. You will need storage, you will need backups, you will need to ensure availability as infrastructure and frontend & backend code evolves, etc. I could totally see a company doing a shift in policy that allows them to clean up their attic, so to speak.