Skim them? Yes. Do they sit around at work reading them as part of their job? No. Their job is to develop games, not really read forums, reddit, twitter, discords, streams, youtube comments, etc.
Yep
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Blizzard, and many other game companies, have an entire team dedicated to collecting that feedback. Those are called Community Managers (CMs). Those are the Blues you see here mostly. They are tasked with collecting the feedback from the forums, reddit, discords, streams, social media, etc. That goes into a weekly report to the Devs, or more often for targeted feedback issues they might want instant feedback on.
Yes.
Bug Reports are handled by Quality Assurance (QA) who take the report, attempt to reproduce the bug, document the bug, etc. That gets set on a priority list and fixed by the Developers. Usually in a Hotfix or Patch. You can report bugs using the in-game Bug Report tool, or the Bug Report forum. That is the only way to get bug feedback to the right teams.
Suggestions/Feedback can be submitted using the in-game Suggestion tool, or by posting on the Discussion portion of the forums where the Community Managers are tasked to collect feedback. Like this forum here.
I don’t know what you mean by rewarding. Everyone would love to know their suggestion was received, and would love to even discuss it with a Dev. That is not going to happen though. Worse, while MANY of the game changes and features we have are the direct result of player feedback, those changes don’t happen fast. They can be a major patch, or expansion down the road. The disconnect between giving the feedback and seeing results is frustrating to players.
Not sure how to change that though.