How did most of the famous servers die?

Thanks everyone for their answers! I guess the main reason is the youtubers aren't playing on them really nowadays.

It just happens. Theres no real rhyme or reason for it, people lose interest and move on.

Well, I don't know. Maybe because they never changes or people are getting bored.

Part of it was some of the servers copying eachother, another part was probably when mojang changed their TOS to stop servers from doing pay-to-win or letting players donate to get an advantage over other players. because of that they probably lost a ton of money and started doing less and less work to keep the servers up

Stopped introducing new and entertaining content is a small part of it. The larger more prevalent reason I think is the poor anti-cheat.

cause once they got some money they just run away and kept it

For this, I'll focus on mineplex.

There are quite a lot of different little things that contributed to mineplex's eventual downfall.

For one, bug fixing took weeks, if not months to patch. I remember one time in a game players enountered a gamebreaking bug, but took a couple of months to fix, compare this to some server like hypixel, where major gamebreaking bugs are almost instantly fixed. Another reason may be that server operations were not as transparent as they should have been. I understand that most large minecraft servers are for profit and dont show much transparency. Lastly, Mineplex lacks constant updates to old gamemodes and additions of new gamemodes. Players will get very bored of the same gamemode with no updates. One of the big factors of hypixel keeping a very large playerbase, is of the constant updates that the dev team pushes.