In terms of real-world performance, not just some synthetic benchmarks, the vast majority of people won't perceive a performance difference between any of those drives. For most use cases, even a SATA SSD should provide very similar performance, as the system will typically be waiting on something other the storage device most of the time.
Just look at the game load test for example. Who is going to notice a half-second difference in a 10 second load time between the Samsung 980 and the WD SN550? There's not going to be any perceptible difference there.
Aside from things like copying large files or transferring them between two fast drives, the typical user is not likely to see a significant difference in transfer rates or responsiveness between any of these drives. And as that review points out, for large file writes that exceed the drive's cache, the (original) WD SN550 actually performed better at that metric, while the Samsung 980 dropped to around 430MB/s once its write cache was exceeded, meaning its sustained write performance was already similar to what the downgraded SN550 does.
It could be argued that the 980 is a better drive overall, but it's highly unlikely that one would notice a "major performance increase" outside of certain benchmarks. Reviewers like to highlight the performance differences in synthetic tests in their reviews, but for common workloads, most SSDs tend to perform rather similar.