Why do people always bring this up when people talk about "Facebook"? Whenever I see people use "Facebook" used to describe the company, I think of all the products they offer, not just facebook.com.

With that being said, anecdotally, in younger (American) circles, facebook.com isn't used much as a social media/content sharing platform. However, other facebook (meta) products like messenger, and instagram are still used a ton, not to mention facebook.com "subproducts" like marketplace, or using facebook pages to act as a landing page for a business. Just because younger people don't use facebook.com doesn't mean they have little relevance within that subgroup.

This isn't even including the huge influence of whatsapp, granted it still(?) doesn't generate any revenue. Facebook developer products like react or pytorch also have a very strong foothold among young developers.