Unless you've got something running in the background it does look like you'e taken a hit.
I "upgraded" to the newer patched version of W10 1909 and took a major performance hit so changed back to 1809
I also found that nvidia driver 417.35 and earlier give a much better frame-rate than any later nvidia driver in BFV.
The downside is multitasking suffers a little. Only noticeable if I'm mining with my GPU. It doesn't leave much in the way of resources for other apps. Chrome stutters badly. I changed drivers back and forth to confirm.
Old driver better for gaming
New driver better for multitasking