I agree that they could have done better. However, I want to give credit where I think credit is due.
When Office 2016 first came out the code base was the same as Office 2011 for Mac. It was a distinctly different code set from Office for Windows. I hated it. I think the first general release build was simply the worst commercial software I had ever used. It crashed. It had bugs. It barely worked at all. I was telling users here in the forum to complain directly to Microsoft's Satya Nadella about how neglected the product was.
Apparently, all our complaints resulted in sweeping changes. During the 2016 product cycle Office, and Excel in particular, underwent a complete remake. They went from 32-bit to 64-bit. The entire code base was abandoned and replaced with the same code base as Office for Windows Word, Excel and PowerPoint. The Visual Basic Editor was rebuilt from scratch (and is still not quite done in 2019). On the Mac side, support for automation via JavaScript and Objective-C was added to AppleScript support. Crashes are practically non-existent. I have used Microsoft Office since 1985 and it has never been as stable as it is today,
I find the number of previously unsupported features that are now supported astonishing considering the short time span since the code base was switched over. The very latest formulas are now supported in Excel - the latest ones being the stock formulas. In Excel 2019 for Mac we now have flash fill, pivotcharts, slicers for tables & PivotTables and PivotCharts, built-in SQL Server ODBC driver, and many many more features.
I think Excel for Mac has undergone the most dramatic positive change of any software I have ever used, and it is evident that Microsoft is continuing to bring it up to par with Excel for Windows. The last remaining frontier is the power tools and accompanying data model piece, which is an enormous amount of coding to work with on a different operating system. They're doing it now! Yay!
While I lament that Office for Mac got way behind development of Office for Windows, I am delighted to see the amount of progress that has been made in a very short period of time. Hence, my advice to nudge the developers to keep at it by giving the feature a vote of support in the UserVoice forum.