Trying to understand where Ethereum fits in with Bitcoin?

Hey all I read this article: https://nakamotoinstitute.org/mempool/bitcoin-not-blockchain/

Makes the argument that bitcoin + blockchain as a unit is the true technology not blockchain alone.

Blockchain exists to ensure immutability however blockchain alone can't do this since you need a currency that has value. The value of the currency + blockchain combined create the security. To hack a blockchain of low value is easy, to hack a blockchain of high value costs so much that it's not worth doing.

Blockchain = decentralized ledger but it's only enforced when we have a lot of decentralized miners and we only have a lot of miners enforcing the system when the currency has value. To ensure a currency has increasing (deflationary value) it needs to remain finite ie the 21M cap.

Some other cryptos also have a cap however most of them don't have proof of work which is the thing that makes it expensive + decentralized = secure. I would love your thoughts on the paper since if this is the case then all the other alt coins running on blockchain are just using buzz words and in the long term are not truly decentralized.

Finally a crypto that has a cap + uses proof of work running on blockchain would not have the same liquidity or security because security takes a lot of time + energy and the longer the system exists the more work (energy cost) it would require to hack it therefore making it incrementally more secure as time goes on.

What are your thoughts on these arguments and how do we make the case for Eth in light of this?

Edits: readability