If you want to make the same game now that you would have released 5 years ago, sure. But games have become way more complex in that time, and the expectations

If you want to make the same game now that you would have released 5 years ago, sure. But games have become way more complex in that time, and the expectations of players have grown considerably. So you end up having to put more content in, more features and more data. The disk and memory become a bottleneck and you need to write and optimise some pretty complex systems to be able to handle that well. PC Hardware has actually advanced since that time as well, so the artists have now more power to create better looking and feeling things in their tools, which means more data to process and get into the game. Also designers will often surprise you as a programmer with the features and creative solutions to problems. They don't really think and design the same way a programmer would, and don't really design for the system hardware (except for the input/output devices of it).