His style was always going to suffer once he started getting older but do you think the game figured him out and other fighters found his weakness or was it a combo of age, slowing down and injuries that led to Cruz slowing down?
"However, on May 7, 2012, Cruz was forced to pull out of the bout citing a torn ACL.
[41]"
"On December 3, 2012, it was revealed that Cruz underwent another ACL surgery after his body rejected one from a cadaver, with an expected recovery time of six to nine months"
"Cruz was scheduled to make his return on February 1, 2014, at
UFC 169 in a unification bout with
interim UFC Bantamweight Champion Renan Barão.
[43] However, on a January 6 episode of
SportsCenter, UFC president Dana White announced that Dominick Cruz had torn his groin and vacated the UFC Bantamweight Championship; "
"Subsequently, on December 22, 2014, Cruz indicated that he had torn the
ACL in his other knee, which sidelined him through 2015."
"Cruz faced
Cody Garbrandt on December 30, 2016, at
UFC 207. After getting knocked down multiple times during the bout, Cruz lost the bout by unanimous decision.
[52] This was the first loss for Cruz in nearly 10 years.
[53] Months later, on
The Joe Rogan Experience, Cruz revealed that he was plagued by
plantar fascia tendinitis throughout training camp that made it difficult for him to walk at times"
"Cruz was expected to face
John Lineker on January 26, 2019 at
UFC 233.
[56] It was reported on December 11, 2018 that Cruz injured his shoulder and pulled out of the fight.
[57] Subsequently, Cruz indicated that he expects to be out of competition for another year"
TLDR; tore ACL, had to have it repaired twice. Tore other ACL, tore ligaments in shoulder and missed over a year. Tore his groin (Ouch!) Had a few broken hands, had severe plantar fascitis.