Indeed ROS Answers is a great community resource and it does rely on the community to give back to make it effective.
In addition to visiting the site periodically you can also sign up to be notified when specific tags are mentioned. So if there’s a topic that you feel that you’re able to help out on add tags associated with that to the “Interesting tags” section in the side bar and make sure you have “Entire forum (tag filtered)” enabled in your “email alerts” settings.
Maintainers we suggest subscribing to tags relating to your packages too. It’s a good way to learn where people are getting tripped up as well as can be an early indicator of a bug or issue with the code.
I’m not sure how you’re computing your ratio, but I find the “unanswered question” filter a little bit more representative of the state of things. Questions that are “closed” as duplicate or off topic will never have an “accepted” answer but also aren’t waiting for one. And the outstanding “unanswered” questions are only 12837 out of 40548 total which is closer to 68% resolved.
If everyone who reads this could try to answer at least one question per week the backlog would be cleared quite quickly.