ND filters? Are you using them?

Am curious who is using NDs for video work, and how did they affect the image? If there is someone using please attach a sample.

I have come to a conclusion that the higher shutter speed makes the image over sharpened which ruins a lot of the footage, it’s noticeable in the shadows and even more in the blacks. ISO 100 sometimes looks like ISO 1600 and I think the high shutter(1/1000+) in mid sunny day have to do with that.

And which ND are you suggesting?