it's just the fact that pure manipulation makes their price (and thus market cap) go up higher than ever.
This is sort of true, but Bitcoin is not completely free either. A very large amount of Bitcoin is in the hands of a few investors, with Jihan Wu for example.
Correct, but Bitcoin enjoys real world usage, while the only sort of usage that the top altcoins enjoy is all in speculative terms. Problem with these top altcoins is that they either set up a fake ICO where they "bought" their own coins for a large part, and the other made sure it possesses a huge amount of coins through instamine. All shady.