I can safely criticize OO's limitations because I understand it and know to use it where it makes sense. That it has limitations does not bother me - every tool in my toolbox has limitations. As long as I understand the limitations, I can prepare for them and avoid unexpected encounters of the painful kind.

For the record, I've written 200 line programs in which OO was worthwhile and 5000 line programs in which it was not. OO is not just for really, really large and complicated applications. OO is for any case where its brand of information hiding and abstraction works in your favour. Based on experience, I strongly suspect that you have encountered plenty of cases where OO would have been worthwhile. However without knowing what that tool could do for you, you blithely accepted the problems from not using it because you didn't realize that those problems were avoidable.

I'd be more specific but I can't be since I lack the specifics of your circumstances. This is why it is important to learn the technique and conciously try to apply it. After you try, seek feedback, think about how it worked, and refine your approach.

Remember the saying, There is a difference between 5 years of experience and 1 year of experience, repeated 5 times. If you're always using the same approach because it is what you know and you think that you don't have time to try anything else, then you're repeating your first year of experience. Furthermore you are shortchanging yourself on time - consistently taking the effort to expose yourself to new approaches saves you time.

Don't believe me? Research has consistently documented 100-fold differences in productivity between programmers. Research on the top programmers demonstrates that they spend less time coding, and more time on design, analyzing what they did, learning about new things, etc. If you're always launching directly into coding because it is obvious to you how to proceed, then you're guaranteeing that you're on the 1 end of that productivity scale rather than the 100 end.

Now some of that difference is ability - you are unlikely to personally be able to become 100 times more productive. But some of it is not. How much of your time is it worth if you could potentially double your productivity? No, I'm not saying that learning OO will double your productivity, on some kinds of projects it will do more than that, on some it is useless. However the attitude that leads you to try it out, when applied consistently to different things, certainly can achieve that doubling over time. And probably over less time than you'd suspect.