PhilH, I think you may be confusing the medium with the message, or at least the messenger.
Your post was thoughtful and well written, with only one typo. I don't think you submitted it to peer review. You were able to produce a good piece of work because you are a good and conscientious writer.
On the other hand, I have frequently had the misfortune of spending $59.95 on a 750 page computer programming book only to find three misspellings and a technical error in the first paragraph of Chapter 1, and things usually go downhill from there. Peer review does no good if both author and reviewer are illiterates.
On the web, there are well written and researched blogs, and others that just dribble off somebody's keyboard. Most are done for fun or to try to inform. Some make money, but I have seen politically edgy blogs start to pull their punches and even edit or delete comments once they have to think about retaining their advertisers.
S&T and Astronomy produce good, high quality writing because they have good, high quality writers. We all want that to continue. What will inevitably have to change is the medium and the business model. I have no clue what that new model could or should be, but it might behoove the writers of both magazines to begin to experiment and see if they can find - or even create - such a model.