Been out of the forums for a while on account of work, but just had to reply to this.
Limiting to HWs, I would actually say Hoost has the LEAST ground for being GOAT out of the trinity of Aerts, Schilt and Hoost.
First lets take out the idea that he should somehow be judged on a curve because he was smaller than the average HW. If we're doing P4P adjustments, there is a host of non-HWs who deserve commendation based on their skill set.
So how do we judge who's the best HW on an absolute level? The simplest way is to just see who was the most dominant fighter and that answer is easy. Schilt has the record on the most K-1 GP wins (4), the fastest GP win (all 1RKOs), and the longest K-1 win streak (13 fights). He was never eliminated from tournament contendership save by one man. K-1 actually had to go around promoting events around the concept of "Stop the Schilt" because his dominance was so assured. They had to make workarounds with the rules with clinch restrictions and then made a sub-100kg belt when those rules weren't enough to stop him from dominating the GPs.
The other way you could consider "greatness" is to look at overall career accomplishments. Based on that, my own pick for greatest HW would be Peter Aerts. Not only did Aerts have a streak of dominance comparable with Schilt early in his career (e.g. 13 fight K-1 win streak, all 1RKO GP wins, consecutive GP wins), he also buttressed it with a long and storied career even after his physical peak. His first win over the #1 guy was against Maurice Smith in 1992 and his last was over Semmy Schilt in 2010 (though he came close in 2013 over Rico). 18 years he was a championship contender! He wasn't just the youngest K-1 champion, he fought long enough to become the oldest K-1 contender. And that time at the end of his career wasn't just empty cash grabs. He was a GP finalist in 2006, 2007 and 2010 with wins over both veterans like Semmy, Remy and Sefo as well as new gen guys like Saki, Teixeira and Zimmerman! Also worth noting that Aerts was the only guy to have a winning series vs Semmy (3-2) despite being so late in his career.
Hoost was held up as the GOAT due only to a historical quirk. For years, he was the only 4 times GP winner so people said he had the most accomplishments. When Semmy won his 4th GP, they somehow tried to decry his accomplishments as if they weren't on the same level as Hoost's (as if being big in the HW division is some sort of moral flaw).
That's built on the presumption that Hoost's 4th GP win was legitimate while Semmy's wasn't. Well Semmy won his 4th GP with 1RKOs over JLB, Remy and Badr. Hoost won his 4th after being eliminated from GP contention TWICE in a year. He lost the eliminator then got to fill in for Semmy when Semmy got injured. He lost the QFs but got to fill in for Sapp when Sapp couldn't continue. In the semis, he checked a Sefo kick and Sefo suffered a freak shin injury. In the finals, he was losing to JLB and JLB's arm gave out! How is a GP win that depends on losing twice but getting four opponent injuries thanks to a voodoo curse somehow legit?
The answer is Semmy if you judge based on pure dominance and Aerts based on career accomplishments. Hoost was brilliant, but he's held up as a foil for Semmy haters not based on simple accomplishments.
