There are many reasons. The easiest one to point at is that STEEM is a social media bubble because it is a social media. nobody bothers to talk about the project that much outside of STEEM front ends.

There is also the bias for BTC and ETH and EOS is only getting attention because of the Ethereum killer narrative. At least http://www.blocktivity.info is honest. My biggest hopes are actually @steemmonsters and @steemhunt If we can promote these two outside of STEEM we may have a chance at breaking into the crypto-mainstream. Few sites like http://stateofthedapps.com with low Alexa rankings won't do much IMHO.

Fiat to STEEM conversion offered by something like @blocktrades or @steemit would actually be great.