Earlier quoted context omitted.
EA is a philosophy, or a mindset. It is not defined by the actions of some group of people that pretend to follow it. There will always be some % of cheaters in whatever human system that exists.
Do you think the same argument applies to communism?
Comparing EA with education is better.
Education is a fundamentally good idea, however, there exist corrupt universities and teachers, e.g. giving students too good grades, just to attract more students and funding. Or teachers asking for bribes.
But that doesn't make education as a concept, a bad idea.
And EA-the-concept: thinking about how you spend any money you donate, instead of following your first impulses and feelings -- that is, like education, a fundamentally good idea.
But just like there are corrupt people in the education system, there are in EA as well.
And there are more in EA (or so it seems), because EA involves more money (and prestige?).