Long, long ago, when Apple introduced OS X they decided to include free high quality email and calendar apps. This was a brilliant decision. Their main competitor Microsoft either did not include or included very poor email applications with their various Windows operating systems. Microsoft wanted the customer to be forced to purchase Outlook, which for all intents and purposes meant they were really forced to buy Microsoft Office. By the way, Apple now includes free office apps with all platforms too.
Microsoft was used to be being a monopoly. They could take this heavy handed approach to a feature as basic as email that should be included with every device. And today, Windows 10 only comes with a compromised version of an email app which makes you want to buy Microsoft Office.
What I personally find odd about this situation is that, for the most part, Mac owners I know underplay this advantage. And Windows users I know have a kind of Stockholm syndrome where whatever email tragedy they are dealing with is what they assume other people have to deal with also. The Mac switchers, really in either direction, are the most likely to realize how great this is for the Mac.
Every computer should come with a high quality free email app. Microsoft will probably find a way to accomplish this, but they haven't yet.