I see about a 100x slowdown on some applications[0] and IO heavy operations with defender in win11. It's unbelieveable how slow it is. I was a huge proponent of it in Win10, but I'm finding it hard to do so now.
[0] The software I'm using does a scan over a few hundred thousand files to read file headers. Without windows defender it takes about 30 seconds, but with defender it takes about 300.
[0] The software I'm using does a scan over a few hundred thousand files to read file headers. Without windows defender it takes about 30 seconds, but with defender it takes about 300.