This request is marked as declined only to avoid duplication and clutter, support for INotifyCollectionChanged will be implemented for our next feature release.  Please follow the other item to get notifications.

There are other important scenarios that also need to be handled and the solution is not simply attaching to the change event of the collection. Here are two examples:

• Not everyone uses observable collections.
• Sometimes a simple List<T> will be modified and the grid can't know about this even if it implements INotifyCollectionChanged. This is often used in custom/external edit forms/scenarios.
• Manual operations on the data as shown here, need a way to be triggered externally.

This is already logged in the following page and we have it under consideration (I have already added your Vote for it, you can also Follow it): https://feedback.telerik.com/blazor/1409112-the-grid-does-not-update-on-data-source-change.

Whether such an interface, or a method like .Refresh() will be implemented on the grid is too early to say, as we have a lot of scenarios to consider (including, for example, manual filtering, sorting and requesting of data).

Thus, I am closing this as a duplicate of the other one.