This makes advertising in those areas more expensive, meaning fewer ads for users in those countries.
It might mean a smaller pool of differing ads, but it does not mean fewer ads for those users. In fact, Facebook might even increase the number of ads shown, because they will be more motivated to do so in order to sell more ad placement.
And the ads they do see will be higher value, from companies that know they can make a return
That is not how advertising works. It's from companies whose advertising managers think they can make a return.
and not low-value/low-return blanket spam
That is not how facebook works. All content on facebook is tagged automatically. When you interact with it those tags are copied into your "interests", whether that interaction was positive or negative. Therefore no advertising on facebook is really targeted, and all of it is just blanket spam.
So up until the point where Meta decides it's no longer worthwhile to provide the service, I call this a win.
And then it's a victory.