if we consider bitcoin currency is the dollar I think altcoin can be regarded as another currency of another country, it is the cool thing they remain connected to each other and exchange between them is good
This is so true, plus altcoins serves as a competitor also to bitcoin, so that the value of bitcoin itself will not be booming so fast, altcoins is breaking the fact of being monopoly of bitcoin as a cryptocurrency.
The bitcoin can learn a lot from altcoins.