It allows you to put a simple FetchXML condition which if it matches will show the button/link if not will hide it. e.g. you can have 2 Edit buttons, one for Status Reason is A and another for Status Reason is B and only show one button or none based on the Status Reason of the record in the List/Grid
Think this is still true, for a List you can get away with just the Filter part of the FetchXML, for a Subgrid need to include a full fetch statement.
<filter type="and">
<condition attribute="statuscode" operator="eq" value="1" />
</filter>