I wouldn't call him an ace he has looks like a LNP artist at times and Hioki had more fights than Takaya at that point and more actual training. It isn't like Hioki isn't a completely flawed fighter too Takaya's grappling is probably better than Hioki's striking at this point and I would pick Takaya if they fought eachother again. Hioki is made out to be some grappling wizard but he loses to or goes to decision with every good fighter he faces. Takaya has been subbed once in his career by Genki Sudo 6 years ago he isn't some can on the ground Hioki will immediately sub.
Loss 15𥑯 United States Robert Peralta Decision (split)
Loss 9𤖫 United States Cub Swanson Decision (unanimous)
Loss 12𤪗 Brazil Bibiano Fernandes Decision (split)
Speaking of losing decisions to any good fighter.
Only Takaya's losses have been in more embarrassing fashion, including being knocked out by Leonard Garcia and Michihiro Omigawa.
As far as going to decision.
Win 9𢴏 Canada Mark Hominick Technical submission (triangle choke)
Win 17𣛨 Japan Rumina Sato TKO (punches)
Win 19𣛨 England Ronnie Mann Submission (triangle choke)
And his win over Sandro was very dominant and Sandro was lucky he escaped some of those subs.
Not to mention, most of Hioki's losses have been very questionable. Especially against Omigawa, total garbage decision.