I feel like another application which is maybe not talked about all that much is that knowing category theory gives you power to name some design pattern, google that, and tap into that vast mathematical knowledge that humanity already discovered. This becomes incredibly valuable once you become aware of how much you don't know. Or maybe just write that bare manimum code that works, idc.

Oh and also when you recognize your design to be something from ct its probably quality. Shit code cant be described with simple math (simple as in all math is simple, not as in math that is easy to understand).