We don't have enough people or a well enough organized proletariat. We need you and people like you to get involved before it is possible. A revolution must be popular, it must be rooted in the will of the working class not a small and insignificant minority that most people haven't had any real interaction with. We can't just do a revolution spontaneously either, there needs to be a revolutionary moment created by a significant crisis within capitalism that just isn't there yet for the imperial core. Trying to start a revolution rn would be an exercise in futility.
This is why we agitate for revolution. This is why we point out the flaws in reformism. It is to get enough people on our side for revolution to be possible. Asking why we haven't revolted already misses the entire point.