You can often find criticisms of narrow technical points, such as TRPF and okishio's theorem. But yeah, generally it seems that the most prolific critics of Marxism are, uh, Marxists.
I'm currently reading On Materialism, which makes a lot of hay on this.
Like Havana Syndrome, you mean?
https://www.webmd.com/brain/features/havana-syndrome
Sure.