I don't think procedural programming itself makes code unreadable. For example, take a look at the redis source code. It's clean and approachable.
I do not find procedural code unreadable, nor is that what I meant to say. Rather the contrary: I said that OOP is only better if the same problem solved in OOP is more readable, which holds only true for a subset of problems.
Regarding the redis source code: Beautiful, truly. I wish more code was that clearly and extensively documented.
OOP is better where you code more readably(in comparison with procedural) and where it makes you enjoy coding more. The conditions for when it does that differ from persons to person and from project to project.
I personally like OOP because it helps me focus on different abstraction levels at the same time, and it helps me stay in the flow.