Those aren't equivalent comparisons. The issues with Ethereum have all been with regards to implementations of applications on top of the ETH layer - parity bug and DAO hack being the two biggest. Neither was due to mistakes in the underlying Ethereum protocol, both had to do with something that someone made using Ethereum.

If I make a vulnerable website it's not nginx/Django/Postgres's fault.

The reason Ethereum hasn't taken over the dominant position yet probably has more to do with Bitcoin's superior brand penetration. Most Bitcoin holders that I know personally have very little actual understanding of how any of the crypto currencies work under the hood, so they follow the general sentiment of the community/press and do not invest based on technical merits.

The DAO hack itself wasn't the problem (in this context) -- the problem was having to deal with a network that does hard forks at a whim in a way deliberately constructed to favor a small group.

I agree that Parity was merely an application on top of ETH, but it was widely used and indicates that users can innocently get snagged by something like that.

>If I make a vulnerable website it's not nginx/Django/Postgres's fault.

If nginx/Django/postgres/PHP have defaults and syntax that make it extremely easy to open up vulnerabilities, then yes, that is a strike against them, and a valid reason to build on a less flaky platform or wait for them to iron that out.

>The reason Ethereum hasn't taken over the dominant position yet probably has more to do with Bitcoin's superior brand penetration.

Or they're people like me, who were excited, then saw the nasty warning signs.