Fix Slicer Performance in Power BI Using Extensive FILTERs:
Swap FILTER with Optimized Functions: Apply KEEPFILTERS, ALLSELECTED, or SUMMARIZE instead of FILTER(ALL(Table), condition) whenever it is applicable to remove row-by-row evaluation on the whole table.
Use Variables (VAR)-Calculated measures that are saved using a variable will avoid executing the calculations again in that measure and improve execution speed.
Optimize Row Context- Any use of FILTER inside the iterators, such as SUMX(), should be avoided. Pre-aggregate data in Power Query or create an indexed lookup table.