Happy with their Choices
He cares what his partner's relatives use because, like many tech geeks, he (and I) want our friends, etc., to get good economic value for their tech investments, and for them to not support corporate assholes.
I understand his partner's relatives viewpoint: they want to throw (perhaps "too much") money at problems they won't want to spend their time solving.
On a practical note, is it possible to easily open a modern Mac and replace the RAM and HD within? Will they work with "standard" RAM and HDs/SSDs?