Some accounts are deleting their posts after a few downvotes. It's devastating on communities like c/asklemmy.
Lemmy doesn't track an account's karma like reddit. So, all downvotes will be isolated to your post or comment and won't affect your account—unless you wrote something truly horrible.
Remember lemmy is a community effort. Deleting a post also removes all comments on it. So you are not only robbing the effort others put in, you are actively removing knowledge from the fediverse. Others won't be able to find it through search and lemmy will seem lonelier than it already is.
Look, I will be honest, I don't like this about social media platforms. Nobody is perfect and not every person universally agrees on everything together. Disagreements and arguments are a guarantee. Who decides what is "truly horrible?" It should be defined in the rules by the mods and admins, not by each individual user.
Downvote a post or comment however you want, sure. But nobody should be following accounts to harass them in other threads or vote brigading every post they make just because they don't like or agree with a post. People do this all the time on Reddit, and Lemmy is no different, they do it here too. This is way more devastating to Lemmy than deleting comments or posts.
If a post or comment actually breaks rules, that is the moderator's and admin's job to take care of. Report it and let them handle it.
Nobody should be deleting posts, I agree, but also please don't be a Brigade Bozo. Nobody likes a Brigade Bozo.
EDIT: Also, may want to add "Why you should know this:" before your last paragraph.