I do miss the spontaneity that existed when games were smaller. It made ideas feel much more organic and flexible, and everything just happened faster with fewer people so you could pivot quickly if you wanted to. Out of curiosity, I looked on Wikipedia and this is the blurb talking about the design of Joust. It's cited as coming from Retro Gamer magazine Issue 63, but sadly it looks like the current publisher has requested it be taken down from the Internet Archive.

John Newcomer conceived Joust as a "flying game" with cooperative two-player gameplay; however, he did not wish to emulate the popular space theme of previous successful flying games like Asteroids and Defender. To that end, he made a list of things that could fly: machines, animals, and fictional characters. After evaluating the positive and negative of each idea, Newcomer chose birds for their wide appeal and his familiarity with fantasy and science fiction media featuring birds. To further increase his understanding, Newcomer went to the library to study mythology. He believed that the primary protagonist should ride a majestic bird. The first choice was an eagle, but the lack of graceful land mobility dissuaded him. Instead, he decided that a flying ostrich was more believable than a running eagle. To differentiate between the first and second player characters, the developers picked a stork, believing the proportions were similar to an ostrich while the color difference would avoid confusion among players. Newcomer chose vultures as the main enemies, believing that they would be recognizably evil. Python Anghelo created concept art of the characters as guidance for further design.