I like what Neels is saying;
* It doesn't look like a technical problem to me, so it probably does
not have a technical solution - no change to gerrit required.
I'd put it like this:
1) Everyone, please review more code. (and comment, and +/-1)
2) Code pushers, take a moment to comment your own commits, if it might
help other code reviewers.
3) +2er people, take a look at who is doing a lot of code review and
consider reaching out to them to invite them to take on +2er responsibility.
k.