The following information provides a summary of the deprecated or removed features from SharePoint Server 2016 release.
The Stsadm command-line tool has been deprecated and users are recommended to use Windows PowerShell for performing administrative command-line tasks. But it is still included to support compatibility with previous product versions.
Support for SQL Express:
SQL Express is not supported for SharePoint 2016. When you install SharePoint 2013 on a single server that has built-in database by using default settings, it will install MS Sql Server 2008 R2 SP1 Express edition and SharePoint product.
SharePoint Foundation is free for on-premises deployments.It is no longer available in the SharePoint Server 2016 release.
Standalone Install Mode:
SharePoint Server 2016 doesn't support the standalone install option and it is no longer available in the setup. During installation you can use MinRole to choose the server role. The Single Server Farm option where everything is installed on the same computer and you must install SQL Server yourself before running the SharePoint Server 2016 farm configuration wizard.
Excel Services in SharePoint:
Excel Services and its associated business intelligence capabilities are no longer hosted on SharePoint Server 2016. Excel Services functionality is now part of Excel Online in Office Online Server (this is the next version of Office Web Apps Server), and SharePoint users can use the services from there(OOS).
Trusted data providers, file locations, data connection libraries, Unattended service account are some of the removed features.
Tags and Notes:
The Tags and Notes feature is deprecated in SharePoint Server 2016 and users cannot create new tags and notes or access existing ones. The SharePoint Administrator can archive all existing tags and notes by using the Export-SPTagsAndNotesData cmdlet.
ForeFront Identity Manager client (FIM):
Earlier versions of SharePoint used ForeFront Identity Manager client (FIM) to synchronize between Active Directory and SharePoint. SharePoint Server 2016 no longer uses FIM as the synchronization client. The default process is Active Directory Import. You can also use any synchronization tool such as Microsoft Identity Manager 2016,
SharePoint BI capabilities:
SharePoint 2016 requires updated versions. The SQL Server 2014 Power Pivot and Power View add-ins for SharePoint 2016 cannot be deployed or used in SharePoint Server 2016. Business Intelligence features like Power Pivot Gallery, Scheduled Data Refresh, Power View reports, Power Pivot Management Dashboard are avaialbe with SharePoint server 2016 if you use SQL Server 2016 CTP 3.1.
New version will not be released for SharePoint Designer,InfoPath. Older version(2013) will be there and supported.