The best way to practice writing is to write, but that doesn't mean that the writing is the goal. I write to communicate, and if you haven't understood what I've written, then I've not met my goal. That's true even if it was still very good practice to write out those words.

I agree with you that unwarranted criticism is unhelpful, and I agree that in blogging, we shouldn't hold others to higher standards than they wish to be held. If you've found a form of writing that brings you joy, then carry on and enjoy it.

But at least for myself, I want to keep on improving in my writing. That's why I (aspirationally) try and learn from great writers like Orwell and Twain, and why I find advice like this useful. I know I'm never going to do this professionally, and I'm quite happy to enjoy writing as a thing for me and me alone, but part of that enjoyment will always be pushing myself to write better.