Maybe investment no longer allows us to make quick profits, but I think that even if we don't invest, we can get relatively stable income from the rewards, but we need to work harder!
When we invest, its all about waiting for when the bull will come, thats the only way you will profit. But it is not good to be relying on your investment since youre already aware that Bitcoin is a volatile asset and youre not sure to which direction it will be going. There are lots of other things one can engage in like trading, cloud mining and many of them.