Speaking as someone who's been on there for years, the process is about as fair and transparent as it can be.
https://en.wikipedia.org/wiki/Wikipedia:BOLD,_revert,_discus...
You make a change, it gets reverted, and then you discuss it. The number one mistake I see new editors make is they don't understand how discussion works and when to seek additional input.
After being reverted, you're expected to start a discussion on the talk page. So many people do not do that, and instead try to communicate through 200 character edit summaries.
But talk pages are just the first step. The next step is to get more people involved. There are a bunch of informal rules which editors have tried to write down on how you can bring more people to a talk page in a fair way (otherwise you would only solicit input from people you would agree with).
https://en.wikipedia.org/wiki/Wikipedia:Dispute_resolution
The typical way this is done is through an RfC, which is a structured discussion between multiple options. When you set up an RfC to resolve a dispute, a bot randomly messages people who are interested in the general area to comment at the talk page. That means you get a bunch of uninvolved editors that don't really have any stake in the dispute and are more level-headed.
The discussion's consensus itself is then evaluated by someone (a closer) who must be uninvolved. In a contentious subject it is often an administrator who has never edited in the topic area before. The closer must give reasons for their decision and an explanation, and there is a working appeals process.
Contrast to virtually any other website where decisions are frequently made by people involved in disputes, you typically don't get reasons for why something is moderated, and you can't effectively appeal to another decision maker as you don't understand the reasoning upon which the decision is based.