Just a thought: most new projects, i.e. the altcoins we have today, do not bring anything new to the table except to enrich the devs, who have these projects milking the life(value) out of existing coins, like bitcoin, which could be why bitcoin is bearish or why it is moving slowly.

What could the long term effects of having more altcoins on the market be, will they help or harm bitcoin?

Exchanges could play an important role in protecting coins that are established to grow from being exposed to shitcoins?