Based on your last paragraph, you seem to be conflating you paying someone with you getting paid. If your thoughts on this subject are that confused, it makes sense that you're not understanding the issues here.

AB5 is about the relationship between the worker and the person paying them. Fundamentally, yes, it's all just compensation for work performed, but the law is all about the specific details of the work relationship not the zoomed-out overbroad simplification you've reduced it to, because at that level everybody is the same as everyone else and if everybody is the same why bother with any laws at all?