Do ERC20-type tokens make a 51% attack more profitable?

Question

A successful 51% attack (PoW or PoS) would allow the attacker to double spend any token, not just ether, so the greatest possible payoff is equal to the value of all ERC20-type tokens plus all ether. But since the only token used for mining/staking is ether, the value of the reward for doing so isn't affected by the value of the ERC20-type tokens. So if the price of ether goes up, the value of mining/staking rewards will too, but the same isn't true for ERC20-type tokens. It seems like the more valuable ERC20-type tokens are relative to ether, the more profitable an attack is and the less stable ethereum is.

Am I right about this? And if so, is this is a known issue?

Answer 1

Double spending affects also ERC20 tokens (and any token types for that matter). It's all about being able to double-send transactions which have some value. I don't see basically much difference between Ether and token in this sense.

I'd imagine that the reason why double spending is always associated with Ethers and not tokens is that Ethers are a lot more widely accepted and have better value. Also Ether is a lot more commonly known than any token.

This is not a secret so in that sense it is a "known issue". But there are not very many tokens which have some reasonable value so it'd take a lot of tokens to make any double spending efforts profitable. In fact I don't think you can have it profitable without gaining Ethers as well - someone else can do the actual calculations.

Answer 2

That's considering that you can mine those ERC20 token when most if not all are not mineable so that makes the attack improbable in the first place.