Why is "Outlook" now being presented as a server-side service on Android?

Conventional wisdom tells us that 'Exchange Server' (or 'Microsoft Exchange Active Sync' / EAS) is a server-side email service from Microsoft, while 'Outlook' is a mail client. But read on ... My primary email mailbox is hosted by Microsoft through a Microsoft 365 business subscription, and I use the Outlook Client on my Samsung S23+ Android phone (Android 14 / OneUI 6.0). I'm struggling to get calendar and contacts sync working reliably (between the Android Calendar and Contacts apps and my Exchange account) so I've been poking around in the 'accounts' and 'sync' settings (which are handled centrally by 'settings' but also by the calendar and the contacts apps, and by the Outlook Client on the phone). In troubleshooting 'accounts', I noticed that Android is now offering an account named 'Outlook' alongside 'EAS' (Microsoft Exchange Active Sync) as a mail server type. Further, the only way I could get 'sync' to work reliably was to enter my Exchange account as the 'Outlook' type. Here's a screenshot showing the setup: The left image shows the 'accounts' I have defined in settings / accounts and backup. The circled EAS account is my email account in question. The second circled account is the 'outlook' account, with the exact same identity. The middle image shows what you see as possible accounts when you choose to 'add an account' - note that 'outlook' is offered as an 'account type' alongside MS exchange active sync. And if you choose that 'outlook' account type, it prompts you for the email address (right image). The key point being, my one mailbox has been entered as both an 'outlook' and an 'MS Exchange Server' type. The 'EAS' account was added first, but I could not get sync to work, so (for reasons unclear now, probably a suggestion by someone somewhere ...) I added the 'outlook' type, and now sync is working! So my question is, why are there two ways to define the same account, and why would the second type be labeled 'outlook', when it's got nothing to do with outlook really - it's just an exchange server account hosted on Microsoft. In the 'calendar' app on Android, I couldn't get sync to work when trying to sync with the EAS account, but when I told it to connect to 'outlook', it started working!