Unfortunately I too have the same problem! I have MacBook Pro(Retina, 13-inch Early 2015) 2.7 GHz Dual-Core Intel Core i5 with 8 GB 1867 MHz DDR3 memory and Intel Iris 6100 1526 MB Graphics, not too fancy, but still a great computer until the last update to the Big Sur... reminded me how my all my iPhones slow down when they get their 2nd or 3rd update.... Apple why are you doing this to us. We will buy your products, just not as often as you want us to.