> the company's valuation has fast growth baked in
That used to be the case. It's trading at a particularly unusual discount today in fact, on a growth to valuation metric. It's radically superior to Amazon on that front. It's better than Google. And it's dramatically better than Microsoft (which barely has any growth).
Facebook is trading for ~23 times likely 2018 earnings. And perhaps 17 or 18 times 2019 earnings.
Google has half the growth rate of Facebook, with a higher multiple (messy earnings statements the past year, but it's reasonably around 30 times 2018 likely earnings).
Microsoft has barely grown earnings for a decade. Their sales growth is single digits. ~30 PE ratio.
Amazon? Ha.
Netflix? Ha.
Cisco has had a contracting business for years on the top line. Profit has also declined. They're being granted a ~20-21 PE ratio on the basis of zero growth. That's barely below what Facebook is getting for considerable growth.
Or take Activision, trading for ~55-60 times earnings, with something around 1/5th the growth of Facebook.
Facebook has a PE ratio a lot closer to Oracle, which has a stagnant business that hasn't increased earnings in years.
Even pathetic Coca Cola, which has a collapsing business (years of sales declines), is trading for ~30 times earnings.
McDonald's which has a business that has been contracting for years, is trading for ~25 times earnings.
Facebook is cheap in just about every way compared to the broad market and compared to most slow-growth blue chips.