You can increase the response rate easily enough, just spend more time answering questions.
The problem is answering questions in a community instead of via customer support is nowhere near as valuable as encouraging members to answer each other’s questions.
This is better known as the organic response rate. It’s the % of questions answered by fellow members.
The only way to boost this metric (without sneakily removing posts) is by making members smarter and more motivated to help each other.
This is why a superuser program is typically the best approach to increasing the organic response rate. You’re supporting and training the very members who are eager to listen and have already indicated a willingness to help.
The more posts you receive, the more superusers you need. If the organic response rate is declining, you typically need more superusers or to do a better job supporting and motivating the superusers you do have.
This makes the organic response rate a far better measure of your work than most other metrics.