Well, for what its worth, I was still able to solo mine 544 coins at launch with a measly 1.2 mash. Yes there were a lot of orphans, but things seemed to work themselves out.

I honestly don't think the orphan rate is that critical of a flaw when you gain INSTANT TRANSACTIONS.

Let's join the 21st century people, everyone expects payment to be instantaneous in this day and age.

If vendors accept a coin with a short block time(like Worldcoin), it wouldn't matter how frustrated the miners got for overwhelming the network with a huge hash rate.
Traders would still trade, holders would still spend and vendors would still convert; regardless of the miners.
The death of a coin is going to depend on the adoption and infrastructure.

One can always see this as a way to discourage too many miners from throwing hashes at the network, and if there is a major acceptance of such a coin due to marketing, promotion, new software and speed.. then it will gain value and the miners will be the only ones with a problem, that is, only if they overwhelm the network.