Does missing punctuation in articles affect a writer's reputation?

yeah! punctuation plays significant role in writing, each has its own role if we miss the punctuation it will create problem for reader to understand it's meaning clearly so, that why put punctuation properly to make sure your writing 

I think if a few punctuation were missing it's not that big deal but it's a problem when the writer does not using them at all and this will show how he/she is not a professional

Writer's are judged on their words - and the rules by which words live by - and so what we actually write defines us and our talent or lack of. Missed punctuation can be just a silly mistake - all writers make them - but not catching it during editing is inexcusable.