I wouldn't call Bitcoin's POW as "trust in algorithm runtime on modern hardware".
Just think about it. The algorithm can be changed by anybody. What does prevent the miners from changing the source code to allow them double spending or even extra coins?
But if they do that and don't have a significant hashrate that do the same, they are on a blockchain fork that is worthless to anybody else.
So we trust in the economic game theory that miners don't tamper with the code.
Just think about it. The algorithm can be changed by anybody. What does prevent the miners from changing the source code to allow them double spending or even extra coins?
But if they do that and don't have a significant hashrate that do the same, they are on a blockchain fork that is worthless to anybody else.
So we trust in the economic game theory that miners don't tamper with the code.