Seems like it. I don't think the correlation described is false.
What you're saying about people procrastinating for other reasons, is the difference between the phrase "one reason why people procrastinate is perfectionism" and the phrase "the only reason why people procrastinate is perfectionism".
As in, people can procrastinate for any of multiple reasons, and perfectionism is one of those reasons.
What you're saying about people procrastinating for other reasons, is the difference between the phrase "one reason why people procrastinate is perfectionism" and the phrase "the only reason why people procrastinate is perfectionism".
As in, people can procrastinate for any of multiple reasons, and perfectionism is one of those reasons.