So we can officially say internet became way too centralized.
Gallery? Use Instagram.
Communication? Only Facebook.
Microblog? Twitter.
Videos? YouTube.
Search engine? Google.
If any of these sites will be shut down, there will be problem for current internet users. They will need to set up new service. And R.I.P. these data. Try to use multiple services for this. You will lose only part if it will get shut down. At least Wikipedia won something once.
It's not like there aren't good, even better options (sometimes), it's just that people are sheep and are all doing the same thing just because everyone else is doing it.