He played in the Masters 20 times, and did not play 4 times when he was probably invited.
In his golf life, he won about 89 times, 29 on Tour, 29 on Senior Tour, and 21 other events like European events, or World Cup, or Canadian PGA, etc.
He was a proven winner, a great player. He obviously won on many courses that were great and not great by his own opinion, and probably won at many exclusive clubs. He had 20 cracks at it. His record shows a best of T10 on two occasions. The ANGC doesn't seem to favor low ball hitters, who preferred playing left to right.
Great champions probably don't like to admit they were just another contender at certain venues.
Would be more believable if he had done better, and had said he was welcomed with open arms.