I can only talk about my Position to this.At the Moment i earn ~600€/Day only with my YT Channels. A few month ago it was kindly between 1000 and 1200€ a Day (but these times the CPC was higher). Last 5 Month Google pays me every Month ~10k€ out (ok ive to pay taxes for this but its ok ... thats life

)
And now a few facts roundabout my Business (without Niche-Details...sorry but its business)
- I started in Dezember last Year
- dont buy Views (or manipulate these otherwise - all natural Traffic)
- dont use Backlinks (or publicate my Channels otherwise beside Youtube)
- dont spend very much Time on my channels (Mosten just simple cloning of other ones Channels)
- use my first Adsense Account
up to the present day (without Proxy or something)
- dont have hundrets of Channels (9 exactly at the Moment)
- got an Payout of ~62k€ (~85k$) up to the present day for complety estimated ~150 hours work (a kind of channels where often deleted in the beginning and ive to reproduce them) ....and the Money increases every Minute without worktimes since ~4 Month for this.
- got ~3 Million of payed Clicks since beginning (400-500k per month at the Moment) - ~20 Million Views complety
If i think about i came to the point that i do exact the opposite of the Tipps ive read here over Month (but be more successfully than the most Board-Consultants who use the Tipps).
After all i think the only realy important Thing is to find an good niche (and im sure that my one is not the "only-perfect-niche").
My Tipp : dont spend to much time in reading Forums for the "Perfect Way to do" but in searching your own Lucky-Niche and make Big Business with this.