Until he fought Berbick (his 28th fight -about where GGG is now) Mike actually had arguably a worse resume than ggg. Given the fact that the HW division in 1986 was considerably deeper than MW is now (ie there were more top guys out there to fight) it's hard to argue that Mikes pre-step up record of 27(25)-0-0 is more impressive than GGGs 28(25)-0-0 at present.
That said, there's no Berbick, Smith or Pinklon Thomas to really step up to in todays MW division. There's just Sergio, unless Golovkin moves up to 168.
Tyson had built up that record under a two year period and was barely out of his teens. Golovkin is in his early 30's, has been fighting for nearly a decade and has beaten just one genuine contender (possibly two if you want to bring up Rosado) in Matt Macklin.
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