Exchange continues to serve as the on-ramp into Office 365 for many organizations. One big reason is the hybrid capabilities that connect on-premises Exchange and Exchange Online.
If you use Exchange Server, it's not difficult to join it to Exchange Online for a seamless transition into the cloud. Microsoft refined the Exchange hybrid configuration wizard to remove a lot of the technical hurdles to shift one of the more important IT workloads into Exchange Online. If you haven't seen the Exchange hybrid experience recently, you may be surprised about some of the improvements over the last few years.