Mustard can obviously speak for himself, but someone needs to point out the facts to you.
Yes, the politics of tennis at the time played a major role in Borg’s retirement. Numerous players have commented on this. I guess this reality just doesn’t make as compelling a narrative as does the notion that he was simply chased out of the game by McEnroe.
From a Sports Illustrated article on the subject in 1982:
Borg's presence in the qualifying—the subject of so much hue and cry among the game's image-mongers—was necessary because of his refusal to comply with Rule 8 in the 1982 Grand Prix guide. It states that a player must commit to playing a minimum of 10 tournaments a year, not counting the French Open, Wimbledon and the U.S. Open, or be forced to qualify for all tournaments. Claiming he needed his "retirement" months and saying he desired more rest later—translation: time to perform in exhibitions from the Falkland Islands to Timbuktu at wages commensurate with whatever the designated countries' national debts will allow—Borg chose to enter seven tournaments and to petition the Men's International Professional Tennis Council to alter the rule. Forehand crosscourt. The MIPTC refused. Volley deep. Borg said fine, he would just as soon not go through the qualies at the French, which he has won only six times, and at Wimbledon, where he's only a five-time winner. Backhand pass. On the line.
Arthur Ashe, who's a member of the council and helped write the rule, last week agreed it was unfair. He said Borg had the ad. "It's one thing to say if a guy doesn't go the distance with 502 plate appearances, he doesn't qualify for the batting title," Ashe said. "This rule doesn't even let the guy come to bat."
Subsequently, Borg and his seconds pressed this point against the sport's ruling alphabet agencies—the International Tennis Federation (ITF) and the Association of Tennis Professionals (ATP) having joined the MIPTC in the fray—until last week, when Monte Carlo buzzed with the drone of tennis politicos searching for a compromise, their blazers and school ties and starch ludicrously out of place on the marble terraces overlooking magnificent Cap-Martin. Butch Buchholz, executive director of the ATP, huddled with Borg. Philippe Chatrier, president of the ITF, caucused with Buchholz. Sir Brian Burnett, chairman of the All England Club, jetted in for discussions with Borg, Chatrier and all the rest.
Would Wimbledon flout the Grand Prix rule and permit Borg to enter its draw straightaway? Would Borg break down and enter three more tournaments? (Significantly, by playing through the qualifying rounds of seven tournaments, Borg probably will wind up playing more—matches if not weeks—to play less.) Was all this nonsense?
Borg, standing on principle, wouldn't budge. "I am not helping them save face," he said.
By this time the sentiment of the touring players, who in a January straw vote had split 50-50 on the question of whether Borg should have to qualify for the majors, had dramatically shifted to his side. "The council treats Borg like they are his parents and he is a 5-year-old," Lendl said. "Bjorn is old enough to know what he should do."
Vilas—as always the poet—said, "The rules were not thinking about this guy, this great champion. Life rules itself; there is balance in life. But this.... We are so sick about this."
