The decline in Ethereum prices has had a very large impact on ICO projects and investors, but I don't think this will affect the normal use of Ethereum, and its low price will allow more investors to buy.
I feel it affects the following:
1. Influence the investor's psychology of investors, when the price of tokens when listed on exchange decreases sharply compared to when they are sold.
2. Previous ICO projects were badly damaged due to the ETH holdings they called from investors, causing many ICOs to be in difficult situation and forced to cut staff.