I am a firm believer in two factor authentication; I can't imagine a better way to keep yourself secure than enabling 2FA on any service that supports it. Contrary to popular belief, there is minimal inconvenience. For any site or service that you care about, the benefits outweigh the cost by several orders of magnitude.
It's worth taking a look at who all supports it and noticing the pattern that that so many "old dogs" (companies that are huge and have been around for a long time) don't support it, but newer companies do. This shouldn't come as a surprise, but might help you decide who gets your business.