This is kind of insincere. They have KIND OF similar resumes, but the devil is the details.
Miocic's best wins:
Werdum
Overeem
JDS
Ngannou
Arlovski
Hunt
His supplementary wins:
Gonzaga
Roy Nelson
Del Rosario
JDS's best wins:
Werdum
Carwin
Cain
Mir
Hunt
Rothwell
Miocic
His supplementary wins:
Cro Cop
Gonzaga
Roy Nelson
Struve
Yvel
Now, on the surface, these are pretty similar. Both have Werdum, Gonzaga, Nelson, Hunt and Struve as common opponents, but JDS inarguably fought better versions of Nelson, Hunt and Gonzaga, and fought Struve in a similar position to Stipe (JDS's 8th fight, Miocic's 10th), and JDS won.
I'll give Stipe the Werdum win superiority, Werdum was HW Champion and had gotten very good wins underneath him, but he was also a top win for JDS, as Werdum was notably the number 1 contender fighting a stay busy fight against an unknown guy, but beyond that, JDS fought most of his top wins at their best or near it. Carwin was coming off a loss but was still a top guy, Cain was undefeated HW Champion, Mir was 3-0 since carwin and just submitted Nogueira, Miocic was on a good rebound streak post Struve, Hunt was 4-0 in his career resurgence, Rothwell was 4-0 in his career resurgence beating Overeem and Barnett. Miocic's win over JDS came as JDS was recovering from injury and was kind of damaged goods, Overeem was streaking but was also notably stop/start, but this is a good win. Hunt had been KO'd bad by JDS and Werdum, Arlovski was on a good streak but hadn't actually looked good in a very long time, and Ngannou was rushed along. Namewise, Stipe has a comparable resume to JDS, but the context of the wins matters immensely, and JDS's work in the division is unignorable.