The number of posts to be reviewed does not stop growing.
Where once it was possible to clear these posts to zero, today that number has passed 700,
and it was lately standing even at more than 800.

However, when I try to do my part and vote on the posts in question, I am quickly blocked
by the limit of 20 reviews per 12 hours (even though the voting message says "24 votes").
It also doesn't help that I am periodically presented with childish "test" questions
and waste my time on analyzing these dummies.

I do not understand where these limits of 20-per-12 came from, but I believe that they are at
the root of the problem of increasing number of untreated flags.

My suggestion is to increase the number of reviews above 20,
for example to 50 as I believe is the case now on Stack Overflow.

I would also suggest a further increase in that limit for users that have achieved the privilege
level of trusted user, perhaps even making it unlimited,
and also to not post test questions to such users, supposedly trusted.

The other limit of 12 hours is in my opinion less useful to change,
as for many users there are normally only certain hours of the day when it is possible
to contribute here. But perhaps making it 6 or even 3 hours would do just as well.