For compatibility with MS-Excel 2016 and upwards, can the FILTER function be added to Calc?
The place for your request is Bugzilla. There is an existing enhancement request to which you could yourself to the CC list
Bug 126573 - Add array functions in Calc: FILTER, SORT, SORTBY, UNIQUE, SEQUENCE, RANDARRAY
Is it only for compatibility with Excel? A Pivot table would cover that functionality, wouldn’t it?
Obviously yes: