Should The Records Of Past Heavies Be Scrutinized & Reassessed Using The Modern Cruiser Standard?

Yes .... but heavyweights don't have weight limit, so even if a guy weighed 187 pounds or 199 pounds in a heavyweight contest there's a difference because there's no weight limit. He might be over-weight or he might be under-weight but that's his business, it's a heavyweight contest. In fact no one really cares whether the scales are right or wrong. You could have a 160 pound guy with weights in his pockets and boots coming in at 186, and a fat 300 pound guy cheating to look lightere and come in at 240, and so what? It's a no weight limit fight. Let them fight. Any weight they like. And fight anyone. It's open.

But ultimately, yes. Over 175 is heavyweight historically, so any fighter above 175 might be called a heavyweight if we want. In fact "CRUISEWEIGHT" was the name used In the British Empire for the 175 pound divsion for many decades, synonymous with "LIGHT HEAVYWEIGHT" which was more commonly used by the Americans
So "cruiserweight" refers to about 4 different divisions - 175, 190, 195, 200.

As for Usyk, sure, but we still have to judge him on how many quality heavyweight contenders he beat. It's fine to say the 'cruisers' are 'heavyweights' too, but how many have proven before or since to be quality contenders in the open division? It's difficult to say where to rate some of them.

Now, for an interesting tangent. Should we rate Wilder as an all-time cruiserweight based on the idea that he "could have" made 200 pounds in his prime?