I have an alternative explanation for the difference in BTC and alt charts. It might not be the mentality of the traders but rather the trading medium. BTC markets are denominated in fiat currencies which are largely stable and have moderate annual inflation. Alt markets are primarily denominated in BTC which is volatile in value and has decreasing annual inflation eventually arriving at zero, hence a market which is behaving deflationary compared with fiat.
These differences in denomination will "color" any difference in mentality between the trading groups and may even eclipse said differences.