That you probably don't even need, but there's a paradigm of "every function should be it's own class" that some devs seem to follow that I will never understand.
I don't do one function one class mantra, but I absolutely need the separate controllers to group methods because each set of them does different things and returns different data. If in my 20+ years of web dev I learned one thing, it's that trying to be too smart with code optimizations and mixing different logic together is never a good idea - it will always backfire on you and everything you "saved" will be nullified by extra time and effort when you're forced to untangle it in future. The whole point of what I wrote was that there's no recipes that can be just uncritically applied anywhere, you need to adapt your style to your particular needs and experience. If you don't need many controllers, great for you... but don't presume you can just copy/paste your own experience on every other project out there, and we all are stupid for doing it differently...
That you probably don't even need, but there's a paradigm of "every function should be it's own class" that some devs seem to follow that I will never understand.