Too much blah-blah-blah. There are two completely different cognitive tasks - ability to read a foreign language, and ability to speak. Improving your ability to read doesn't affect your ability to speak. You should train both of them separately.
The ability to read other people's code doesn't help you when you must write your own. You can read, say, tens articles and blog-posts per day, but it doesn't affect your ability to write one. OK, in the long run it does, but only after long practice of writing.
Resume: Reading a book or watching an online-course without doing a home-work or exercises is a waste of a time, because writing (composing) is a completely different cognitive task.
I don't suggest just reading code, I suggest reading code
critically, with an eye to how it can be improved.
You're right that casually reading 10 blog posts doesn't help one's writing. But reading them carefully and critically, trying to concretely identify how the author has crafted the language to support their goals? I believe this absolutely can improve one's writing; indeed, I think it's an important part of improving.
Yes, of course, you still have to knuckle down and do a lot of writing at some point, too :)
The ability to read other people's code doesn't help you when you must write your own. You can read, say, tens articles and blog-posts per day, but it doesn't affect your ability to write one. OK, in the long run it does, but only after long practice of writing.
Resume: Reading a book or watching an online-course without doing a home-work or exercises is a waste of a time, because writing (composing) is a completely different cognitive task.