Ronaldo left Old Trafford for Saudi club Al Nassr in January, having lost popularity under Dutch coach Erik ten Hag.
The Portuguese international was the season's top scorer before Ten Hag's arrival, but was seen as redundant under the Dutchman and was discarded a few months after the former Ajax manager's spell at United.
Chilean midfielder Arturo Vidal believes Ten Hag's decision was wrong.
Vidal, who currently plays football in Brazil with Atletico Paranense, was asked about Ronaldo's situation and defended his departure from United, while also attacking bald coaches, whom he described as "complicated".
Referring to Ten Hag's arrival in Manchester, Vidal said: "This coach came badly. How are you going to eliminate Cristiano Ronaldo? So are these men. He was the goalscorer and he took him out," he said, adding: "Bald coaches are very complicated."
Vidal's accusation of the bald coaches stems from his time under coach Jorge Sampaoli, who managed the Flamengo midfielder last season.
The 36-year-old won the Copa Libertadores and the Copa Brasil in his season with the club, but has only played 21 games and has often been ignored by bald Argentine coach Sampaoli.
In his debut for Atlético Paranense, Vidal criticised Sampaoli as a "loser" and accused him of not appreciating his players.
Ronaldo returned to Old Trafford on a free transfer from Juventus in 2021 and scored 24 goals in 38 appearances during his first season with Manchester United, earning a place in the PFA's Team of the Season.
However, after Ten Hag's appointment, the Portuguese star struggled to make regular appearances as the Dutch coach was looking to put his own mark on a team that was struggling to reach a "new identity".