21% of all Americans live in common-interest housing. Half of that is condominiums, half is HOA-governed housing. It's a safe bet that large portions of that heavily restrict lawn conditions. Add in another ~10% of the country living in multi-family apartment buildings, which usually have no lawns or owner-controlled lawns.
And, of course, single-family home lawns in any densely populated area are likely to be regulated, many of which aren't high income. I can't get numbers on how many of those ~70% of Americans are under town restrictions, but it's not a trivial number.
So no, it's not just HN's demographics. This is genuinely widespread in the US; I'd estimate that at least 100,000,000 Americans live under some form of these restrictions.
Homeowners on HN are wealthier and live in more densely populated areas than the average American homeowner. Wealth directly correlates with minimum standards of upkeep. Population density correlates with volume of rules and regulation. A suburb of Portland ME and Portland OR both likely have a bylaw disallowing you to run a pig farm without some paperwork/approval.
A suburb of Portlad OR is far more likely to have a bylaw or HOA reg about grass height or some other nit picky thing than the suburb of Portland ME because the OR suburb is wealthier and wealthy people have the time to care about these things, care about what the standards should be and care about how to enforce them.
Yes, many Americans live somewhere one or more rules/laws that control what they do on/with their own residential property. The Americans who are most represented here likely have far many laws/HOA rules with which they much comply.
Sure, agreed, but that's not what you said before.
Someone said it's "somewhat common in the US" to be restricted from growing eco-friendly laws. You "fixed" that statement by adjusting it to "somewhat common in the US in the parts of the US that are over-represented on HN".
The initial statement was true, there was nothing to fix. It might be "very common" among HN readers (though I'll bet they skew more urban than you're suggesting), but it really is "somewhat common" nationwide.
And the distinction isn't irrelevant, because this isn't just a parochial HN-reader concern - turf covers roughly 2% of US land. Not all of that is lawns, and not all of those lawns are legally constrained, but as I tried to demonstrate, the total amount is significant. I'm not objecting to the point that this situation has heavy demographic skew, I'm objecting to the implication that it isn't widespread.
Keep in mind the "more free" places also tend to be much less dense in general (not just fewer HN readers, fewer people in general). So even if it's relatively geographically isolated where these rules exist, it still covers a substantial portion of Americans (including HN readers).
FTFY.