Naive question about Proof of Stake in the context of Algorand

General
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1

I am new to Algorand and I am trying to learn more about the consensus protocol. As I understand, Algorand uses a VRF to choose validator nodes. The chance of being chosen as a validator node is directly correlated with the amount of $algos in your account.

The market cap of Algorand is about $8 billion. Theoretically, could an evil multi-billionaire buy up 80% of the supply of Algos, thus increasing his probability of getting chosen to verify the next block by the VRF? In this scenario, the evil billionaire could append malicious blocks containing double spending and corrupt the ledger. Of course, the evil billionaire would loose all his Algo investment because he has corrupted the ledger that he has a huge stake in. In this scenario, he does not care about that. He only cares about the demise of Algorand.

Is this scenario possible?

I have read through the Algorand consensus - Algorand Developer Portal, but this kind of scenario is not clear to me. Can someone clear it up for me?

2

This is indeed a potential issue with any proof-of-stake blockchain.

That being said, the price to pay is most likely larger than $8 billion as when the billionaire starts buying, the price may increase quite a lot.
Furthermore, many Algo-holdees hodl their Algos and will not necessarily want to sell at all.

Note also that a similar attacks apply to proof-of-work blockchains: instead of buying the tokens, you pay the miners and/or buy enough mining equipment to get 51% of the mining power and fork the chain.

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