Actually I would say that egalitarianism recognizes and honors individuals without imposing collectivist ideals, whereas elitism is collectivist in that the elite are the ones who are best at submitting to and embodying a collective ideal. Your mileage may vary.
I do agree with the article's assessment of the Theosophists role regarding this.
Elitism is basically a caste system idea, although execution varies within the different types of government and social situations. (Same thing, many forms... go figure) It's basically establishing an authority and projecting conformity -- it's very non-LHP ultimately if the criteria were to encourage a manifestation of LHP values within society for the sake of progress, for example. In any case, in the typical LHP use you have a bunch of edgelords that assume that anyone not in their thought posse is full of beans. It's just a delusion, but hey you can't stop stupid!
Egalitarianism is sort of like throwing the baby out with the bathwater. We know some individuals are relatively useless or dead weight, but this idea basically says we should respect everyone or consider them of equal worth. It just doesn't stand up to any scrutiny at all, but it sounds really good on paper. Basically, to give an idea why this doesn't work -- someone who flips burgers is consider equal to someone whom does open heart surgery. That's just nonsense, anyone can do the former, but the latter is a rare skill that requires several years of rigorous training and a constant dedication to new technologies and research as well as their application.
I think most LHP-types are screwing up the last concept with what they mean with altruism most of the time. Altruism is just a non-addressed subject at least in the context of the Western or Eastern LHP, but the elitist edgelords are going to have problems with it because they see it as combative to their notion of stratification. Again, this is just an error of logic since we can be rich and elite while still being kind to the less fortunate -- if we have achieved such lofty heights then being generous has little effect on us personally other than to promote a good public image. Basically, it just comes down to whether selfishness is a valuable trait, and in most cases I'd posit that it isn't. It makes you seem petty, vile, and trivial. You cannot be elite at least in a real way (with support of the collective) without being a good master. You have to give something back for the public at large to recognize your value, and accept your place in the order of things.