Metas are already happening.
This is 6v6 competitive play in professional teams. Try that 2xWins2xLuci2XTrac combo in comp. normal queue and see if it works (hint: no, it fails miserably, because their tracers won't get through your frontline, and your zarya + reaper will tear the winstons apart, lucio or no)
so does League and DOTA
Should've clarified that: The people are IN THE SAME SPOT in overwatch (unless they are bad, and if that's the case well, sh** happens man. They are not dispersed across three lanes, so coordinated movement is a bit easier.
As to people chasing KDA: Again, bad players happen.
I've seen more demands for fixing the scoring system, the leavers -and- the way coin flip works than I have for DQ removal.
That's the point I can agree on.
Because, DQ is present in OW, but as you said: Its simply not a big deal. Yes, we would like to see it removed, but due to the aforementioned factors, its simply not a big deal.