2) In 2017 people knew Bitcoin only from his growth-side. If the crisis of 2013 was recalled, it seemed like something long forgotten. Now every newcomer will remember crisis of 2018 and will think 100 times before investing big money here.
In 2018, Bitcoin is not the first crisis. If you look at the dynamics of the course for the entire existence of the coin, you will see that this is already the fourth crisis.
There has been many before but those happened without people's attention. How many are even aware that btc exists then? Now 2017 thrusted btc to everyone's attention and people have seen now the crash this year. If you're someone looking from the outside, that is not a very attractive prospect if you're thinking of getting in.