That and the fact there are no incidents reported or documented to dispute their own claims. If you have other elements or infos, by all means...
What claims? They haven't made any. You're presuming that most artists aren't thin-skinned individuals who dislike criticism based on the little you know about a few members of Genesis.
Whereas I, who have worked in the business since the mid-nineties, have given you an informed opinion that being sensitive to criticism is endemic in the arts. That's not enough for you? Fine, continue to presume the contrary if it suits you.