I think trying to say in an educated manner "xxx wrote about it, it must be true!" is not a healthy thing.
Altruism has nothing to do with destruction, and the logic that it does is flawed and outdated.
Modern definitions of altruism consist of kind acts without a material gain. Technically you may be "altruistic" if you give someone a house to live in and then terrorize them as if they belong to you, because you've gained no materials (following your definition of altruism), but this isn't what I would consider altruistic because it involves an ulterior motive in which the person you help suffers as well.
The problem with philosophy is that every philosopher has their own ideas and ideals, as well as definitions. If we had a clear definition of altruism that everyone would agree to, then we could begin to discuss whether it's a crutch or if it's possible to be altruistic at all.
I do not agree 100% with what Kant said, and I refuse to believe that a charity act, with no material gain, is considered destructive in nature. To imply, or even state that acts of giving are in essence self destructive, is to ensure that humanity as a species will not survive the next thousand years due to selfish greed, jealousy, and malice.