The primary content no user wants to see any every user agent would filter out is ads. Since ads are the primary way sites stay in business, they are obligated to fight against user agents or other intermediary systems.
The ultimate problem is that Facebook doesn't want to show you good, enriching content from your friends and family. They want to show you ads. The good content is just a necessary evil to make you tolerate looking at ads. Every time you upload some adorable photo of your baby for your friends to ooh and aah over, you're giving Facebook free bait that they then use to trap your friends into looking at ads.
The primary content no user wants to see any every user agent would filter out is ads. Since ads are the primary way sites stay in business, they are obligated to fight against user agents or other intermediary systems.
The ultimate problem is that Facebook doesn't want to show you good, enriching content from your friends and family. They want to show you ads. The good content is just a necessary evil to make you tolerate looking at ads. Every time you upload some adorable photo of your baby for your friends to ooh and aah over, you're giving Facebook free bait that they then use to trap your friends into looking at ads.