How Does the Cost of a 51% Attack in PoS Scale Compared to the Cost in PoW?

The cost of a 51% attack in PoS is directly tied to the market capitalization and the amount of staked capital. The attacker must acquire over 50% of the staked coin, plus risk losing it all to slashing.

In PoW, the cost is tied to the rental/purchase of hardware and energy, which is independent of the coin's market cap, making it cheaper for smaller coins. PoS scales security with the coin's value, making a 51% attack exponentially more expensive for large-cap coins.