I can understand why TS feels that way, but he's by far the only one, and for the most part people seem to be split about 50/50 on this fight.
It's just that Mousasi has one of those starry-eyed, irrational Sherdog fanbases that very vocally touts his upcoming domination of whoever he's facing next and are seemingly only counting down the days until he achieves GOAT status. He's got that overseas mystique, and he's buddies with Fedor. That in itself gives him a built-in legion of huggers. Oh, and he's fought some K1 fights, so that automatically makes him the best striker in the division
In truth, he's a very talented guy with an impressive record and tons of potential. Has he really beaten anyone of note or fought top-level competition? No, not really. And don't start rattling off names that you THINK are top-level, they're not; most were either very green (Jacare) or very over-rated (Manhoef, losing-streak Hunt). As for the K1 thing, it doesn't always translate into MMA striking; ie: Overeem, Barry, Manheof.
Machida via TKO or UD