The problem with Altcoins is that the market was saturated with ICO's and cash grabs with no real-world products to support their model long term. So many people have been burned time and time again, there is little investment happening in the Altcoin space compared to earlier this year.
Altcoins aren't dead, just the ones with poor leadership, transparency, and solid user-end products.
Thinking about this too. There are a lot of altcoins everyday and most people invest on it for months, that's why their funds are in there until the ICO becomes successful but what if your investment turns bad? It's a waste of time and probably money even if your investments gets refunded. Having a lot of altcoins is also bad for crypto.