Idea lab still has items from Classic that are no longer relevant. It also has lots of duplicate or near duplicate ideas. If you have 10 ideas that are the same with 300 points each vs. one idea with 3,000 points, that's a HUGE difference. Maybe create an Archive section for the old stuff or non-relevant stuff and then combine duplicates (and their points).
Now there's an idea!
That being said, when you have items that are delivered with only 20 points and then items not under consideration that have 500 points, it erodes the credibility of the vote system. People tend to give up on it knowing their idea won't get done even they garner a lot of votes.