I have a 2TB HDD that was ntfs and now ext4 as well. I can't say I've noticed a difference, but I didn't do any benchmarking either.

I wouldn't consider ntfs as malware like I would something like anticheat software. As far as I know ntfs doesn't intentionally or negligently harm, open a system to harm, or perform tasks that have nothing to do with the designed function.

Drefragging sucks I guess, but it had to be run so infrequently. I can certainly understand why someone would want to move onto something that removed the need for it.