Why do I always hear about dementia drug "breakthroughs" but nothing seems to actually change?

I see news stories ALL. THE. TIME. claiming there's been some amazing "breakthrough" in medications for different types of dementia. 

So why do I rarely hear about those medications actually being prescribed? And do I never seem to see these miraculous, positive changes in my dementia patients?

This video by Healthcare Triage talks about a new Alzheimer's medication that created some controversy last year and why we need to take those "breakthrough" news stories with a healthy grain of salt.