And in turn none of the discussion you've replied to is relevant by your standard, because the OG article discusses the United States.

Funny someone else is allowed to discuss UK in regards to an American article, but I'm not allowed to discuss America on a UK thread about an American article.

The discussion was prompted by an article on sharehouses being banned in US cities, which prompted comparison to HMOs in the UK. One of those comparisons suggested that HMOs are a recent phenomenon and are a cause in the shortage of family homes in the UK. I replied to this by arguing that a shortage of family homes was also present in the 1970s, and that overcrowded housing for working families has been common throughout British history. You've replied to this with your personal experiences about building a home in the 1970s and dealing with building regulations.

The discussion about the effects of UK HMOs on wider housing availability is indeed a peripheral discussion of limited interest to most. Your comment, while of interest to me, was only tangentially related to my comment. I'm not arguing that you shouldn't have written it - as I said, I found it interesting - I'm just pointing out that it doesn't flow well from what came before it.