Almost all computer hardware is sold within a range of specs, not absolute specs. The silicon lottery is a thing, and what you get could be exactly on the spec or above it to some level.

As long as all the providers meet a given spec, if some of them are better that isn't inherently a problem. This applies to having different suppliers as well as variance within a manufacturing process.

Now, of course if all reviewers happen to get the better version this could be an issue, as seen with lots of SSDs recently with components getting swapped out after-the-fact.

Of note, Samsung use different chips in different markets. The US version of the Galaxy S20 uses a Snapdragon chip which is generally considered better than the EU version's Exynos chip, particularly when it comes to power efficiency. That caused some anger.

I would say that as long as a manufacturer handles it correctly with reviewers so consumers see the minimum they could get, not a best-case, it's fine. Otherwise, it should probably be sold under a different name.