If you mean improvement vs. SATA, that would be incorrect. IOPS and latency are both massively improved by NVMe.
Here's an IOPS graph from one of the best SATA drives vs. QD=1 and QD=256 IOPS from one of the fastest NVMe drives:
So, 4k IOPS approximately doubled at QD=1 and improved 15x at max QD!
That said, if you're not running a server application of some sort, you probably don't care about that high QD IOPS number. However, a common pattern we see in software is to have a bunch of IO operations that are interspersed with computation. In such cases, the latency of the individual I/O operations can definitely limit overall performance (i.e. if the OS is unable to hide it via prefetching).
I didn't find separate measurement on the Samsung 860 Pro's read & write latency, but you can estimate the value for Read based on the QD=1 IOPS. So, that would be roughly 82.2 usec or just over double that of the faster NVMe drives.