How much does mining and dumping affect the long term viability of coin?

There has been some discussion about the effects of auto-exchange multipools and services like
Nicehash on the survival of altcoins. Many believe these services "kill" coins.

From my perspective coins will live or die on their own regardless how how they are mined. Mining only
affects mining.

Why is a coin overmined? Simple, because it's profitable to do so, which is a good indicator of the coin's health.
It means there are buyers. If the buying dries up the price drops and mining becomes no longer profitable.
Trading volume is good even if much of the sell volume is auto-dumping.

The biggest impact of large mining operations is dramatic swings in hash rate as hash moves from one coin/algo
to another. Coins need to be able to adapt to these changes in real time in order to maintain a reasonably constant
supply of new coins. Coins that fail to do this will die.

Auto-exchange pools, Nicehash, large farms, rentals are a real part of mining and coins have to be designed to take
this into account if they want to survive.

Light your flamethrowers...