One reason why games are getting so large is because all the high-quality artwork that is present in AAA titles really takes up a lot of space. Games like Forza Motorsport 7 feature over 700 cars with unique artwork that has to look good at 4K resolutions, and a title like Titanfall has 35GB of audio files alone.
However, there are also some critics in the game dev industry who believe studios aren't doing enough to keep installers small. There's a sense that some game developers have forgotten how to develop smaller assets, as they assume that everyone has a huge storage disk and superfast broadband Internet.
Last decade, game developers still had to worry about how they could fit all the game assets on a CD or DVD. This is no longer the case due to digital distribution and this leads to complacency as developers aren't putting in their best effort to keep the size small.
There’s also a disconnect between developers and their audience. “Games are developed in big cities, by young people in tech-hubs where the studio has fiber, everyone has fiber, and the idea of download size mattering is laughable,” Harris said. “It’s not a concern they can identify with in any way. Plus, there are still some idiots who mock a game for being a small download size. Yes, that actually happens.”You can read the piece over here.
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“That means leaving sound as Wav files instead of (way smaller) OGG files, using HD textures even for tiny elements that are never seen at full size…” lamented Harris. “[They also] leave mip-maps on when they won’t be used, always use 32-bit color when some textures are greyscale, and even ship audio for 10 different languages to everyone, regardless of region.”