Possibly. The way I see it, MS used to have 90%+ of share of a much smaller market than what exists today. If they end up with, say, 20% of paying customers for Mobile/PC+Gaming, it will be more than enough for them to be bigger and more profitable than they've been so far.
Amazon seems to be comfortably building vertical integration in their role as the biggest retail (and logistics) operation in the world, so I'd expect them to stick around in the top 5 for a long time until China comes up with the biggest retail operation ever.
Apple might take over a nice upmarket slice of the auto market and remain on the list.
Google is so weird they might split into 4 companies and take more than one place in the top 5.
I have this feeling that Facebook might be the least difficult to displace, as Netflix and other games&media companies develop the "social" side to what they offer today. then again, FB should at some point add a consumer electronics component to what they do and become a BIG player in an expanding VR+gaming market.
I'll set a calendar reminder to review this post in 5 years so I can laugh at myself.