Hello dears, I saw in the description that there's no downvote system, but I still see the downvote button and it makes a difference, I used it somewhere (then took it back)
Some instances have downvotes disabled (blåhaj, and reddthat are two that come to mind). Users from other instances can visit and downvote, but they are not federated with the original instance. Some apps allow you to customize what you see. With Mlem I can hide the downvote button, as well as any downvotes.
I believe piefed allows moderators to disable downvotes for each community, rather than an entire instance.