It is the unfortunate consequence of having a public platform. Some parties have a stake in seeing it fail, or want to use it selfishly at the expense of everyone else.

These can be competitors, criminals and big companies who rely on everything being under their control.

This is why good moderation is important and having something like adblock or a simple filter is a thing I do recommend. Note tho, just like any platform that doesn't pay their moderators, some lemmy spaces (and sometimes it's mods) are quite a mess.

Sometimes it's because orgs that make millions just decide to be irresponsible and hoard wealth (eg, wikipedia) and sometimes it's because it's run by volenteers (like a good chunk of lemmy, mastodon and matrix)