I was a mod on a reasonably large subreddit. One day, someone decides to post links to extreme and shocking images but make them look like regular posts. Delete, ban, move on. They come back with a new account. Delete, ban, move on, implement limits on new accounts. They would then spend months warming up new accounts, using them to write regular posts and messages, before doing the same thing. This was a thankless task and most regular users never realized it was even going on.

Then, on the other side, there were people who absolutely lost it when they felt you made a bad decision. I deleted a post asking for cash under the table work in a local sub, combined with multiple people offering what looked like clearly illegal work. Multiple regular members of the community went absolutely crazy, as if I had personally wronged them.

I enjoyed running the subreddit but I had to give up. The person who took over after definitely enjoys the power a little bit too much. That's what you get when it's a volunteer gig.

So, if the admins of the site to a really good job of banning accounts that exist for the purpose of vote manipulation, then voting works ok. If not the votes that generally dictate how well a post/topic does occur within the first few minutes of posting.

Post topic -> Upvote -> Post conformation messages of approval of the topic -> bots upvote these posts -> bots downvote anyone that disagree.

Moreso, downvotes themselves don't directly address things like raids and sustained attacks by bad actors. These kinds of attacks make the end user feel like they don't want to be in that subforum driving them off elsewhere and lowering participation. It can also embolden others to post more similar content to what the bots are posting.