It is wrong to assume that crypto is broken if it doesn't have a high value in some arbitrary currency like the USD. Crypto works just as well even if the price 0. It will still process transactions, still create new blocks, and it will still have a use for someone somewhere, even non-financial.
There's little incentive to mine if the price is zero. It would be much easier for a single entity to undermine the integrity of the chain with a 51% attack if the only miners are true believers not motivated by money.
0 here is a figure of speech. Chains never go to zero if they are still alive, they are always worth something to someone, even if they are test-nets.
Also, high price of a token does not mean the security is high! What matters is that the participants stay honest. See section 6 of bitcoin.pdf, also nowhere in the paper it mentions about price!