Actually there’s a lot more to changing the rules after the fact.
Depending on WHERE the HOA/POA is located .. and the way the by-laws are written. In our association it CAN be done - but it’s a matter of getting the majority of property owners to agree... hahaha ...like that’s going to happen. There was a time limit on when our restrictions could be changed ... and the ONE year the board had the opportunity to change them they did NOT take the opportunity to attempt to do it.. so it will be another 10 years I think before the opportunity arises.
It really depends on the HOA/POA... if the rules can be changed .. generally though it is so much trouble it’s a pain in the neck...
LOL! 'Pain in the neck' (or some other choice of anatomy) would describe 99.9% of bureaucracy.
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What most folks don't understand is what a nightmare this creates for the HOA.
If the HOA allows them to stay, it is in violation of its contract with everybody else because of its failure to enforce the rules about minors living in the community.
Like you stated, getting everyone to agree to a change in the rules is ludicrous, so the HOA has no choice but to enforce its own rules...no matter how swiftly some people want to label it as a 'heartless' act.