I think it depends on the subject. And the personality of the person. I envy and admire your ability to be so carefree about what you write. A typo or gramatical error shouldn’t affect how the author is viewed as a person or even the credibility of their post. As you said this isn’t “academia”.. nor is it a professional environment.
The only time I’d say that a grammatical error or typo might be detrimental to a post, is when it affects the meaning trying to be conveyed.
So if I ever do offer you a correction please don’t hold it against me haha
A couple of typos or missed commas wouldn't make me just a post harshly. The post above was written pretty well. However, I do think there are people here who should proofread at least one time or work to improve their use of the language they are writing in. I'm NOT talking about this post, but there are some posts here on Steemit that are written with such poor language that they are almost incomprehensible, and that does poor service to the readers and the writer. Also, adding in some subheadings, shorter paragraphs, and bullet points make things easier to read online, so they are bound to keep the attention of even more readers.