Compare that example to some of the more recent bannerlord threads where lots of people are defending the new combat system, and a handful of people who have valid criticisms. The former vastly outnumber the latter. The problems with the combat system are fairly minute, but they drastically lower the skill ceiling.
- With an upvote system, people who don't know how to argue their point will just take to the arrows.
- With the comments alone, you actually have to read the damn thing and make up your own mind whether somebody is correct or not, rather than letting the arrows influence your opinion.
The problem here is that people are already biased.
With a long standing forum such as this one, there are already dynamics between long time users.
I ,as a fairly new (active) member to this forum, can sometimes find myself being biased towards, recruts, people without profile pictures or pictures I don't like. If a rekrut is in a discussion with a member which I value more, I might be subconciously influenced to support either side.
And to be honest I don't think that everybody goes through all the conversation even though you should. Posting without reading is just easier.
The chance of an upvote system could be that it is anonymous. - However, I think an upvote system should only be in place for suggestion threads.
Suggestion threads are in need to be active so that developers or modders can see them. They have to fight for attention until they are recognized, I think that's why +1 is often spammed there. A voting system could work as a different indicator instead of the numbers of replys on such threads.
And while suggestions can cause discussions most of the time you are either pro or contra a suggestion. Also an upvote-system doesn't habe to exclude people from actually writing (as others have said before) And last but not least, with suggestions, the final decision to implement something is always with the person to implement a change.
A problem with the system could be that suggestions with a low count could be ignored by the majority of readers. But that is already a problem and I think it's impossible to solve.
I don't think that an upvote system should be in place for any other threads such as discussions or off topic.
Generally I am also think that a forum should be a place to talk and interact and while I do think that any form of bias can have a negative effect on all discussions, a like-system is not a solution here.
TL;DR :Like-System only for suggestion-threads, discussions and everything else should stay as they are.