I totally agree on this. Everybody who is using other model driven apps naturally tries to filter like they are used to. Especially the "contains data" or "Begins with" would be super helpful because it gives a wider range of flexibility when setting up the calculation.Also the user interface makes you believe that you can filter whatever you want because it is looking exactly like the advanced filtering from the model driven app tables. The only reference that you cannot do that is in the official microsoft documentation.If it's not possible to change that at least a visual hint for the users would be nice - or a check before the calculation is saved. I found out that I can set the filter to "not allowed" values, and then run the pcf calculation without any issue but I don't get data out of the calculation, which I only can see after the calculation is finished. This is not a good user experience :(