The whole crypto will always act as one. It is not because of individual characteristics of each coin but it is because of human behavior. We humans tend to group things together so that in the markets, industries fall and rise together.
Good point from that part as the hole industry was supported by investors and there's always people who will keep bringing new ideas but will also
take part of the original concept. Alts will depend from bitcoin and bitcoin investors will look after alts to bring something good from their investment.