There's a difference between giving advice and sharing your experiences as you learn.
I think a lot of people who write about writing, especially on Medium, are simply sharing their experiences and what they've learned along the way. Somethings we would have all heard before, others, we can take onboard and apply to our own writing process.
Of course there are always going to be writers pushing back - usually those who consider themselves professionals - and saying some people have no right to share their limited knowledge, but that's their problem if they don't like it. For most, we are just having fun as we aim to improve our skills and share our journey along the way 😁.