The HOA or landlord can modify the terms, but they're disincentivized to do so.
The reason that both HOAs and landlords disallow outdoor clothes drying is that it's seen as an eyesore. People associate clotheslines full of clothes with images of testaments in NYC in the 1920s and representing overpopulation and or immigration.
Landlords in particular don't want people hanging things from the apartments- even objects like small satellite dishes are often not allowed.
What many don't know is that in the US, many of these rules are simply null and void:
https://www.sightline.org/2012/02/21/clothesline-bans-void-i...
The challenge is that this requires a great deal of work on the part of the homeowner, and in doing so they would be entering into a conflict with the HOA. They would win in a court, but they would need to put up the money to fight in court. Even if/when they won, the HOA would make life unpleasant for them and likely retaliate in some other way.
