"I did it, so everyone should have to do it" is a mindset that denies the possibility of progress to something better.

The mischaracterizes what I'm saying. I'm not saying everyone has to do it. Nobody has to do it -- it's your choice. What I'm saying is that doing it can give you an advantage.

> True, it's a lot of work. But plenty of people (myself included) manage it.

Generally what the person recruiting ate for lunch and the state of their bowel has ten times the influence on the success of your application than any amount of time you spend writing a cover letter. It's all random, and you can't know beforehand if your application will arrive at a serious recruiter or not.