Wiki reorg: Edit Comparisons

[filippoweb3]

Major reorg to the comparisons section.

[filippoweb3]

@mmagician I am making a comparison in the wiki between ZK, Optimistic, and Polkadot rollups. I know you are working on ZK rollups and I would like to ask if you can provide a review on the content of this PR 🙏

[CrackTheCode016]

Looks over all good, maybe we should mention ELVES at least one though, as that's the formal protocol that parachains follow. It would be nice to incoprorate a comparison of that somewhere here!

[filippoweb3]

@bLd75 review includes:

Can’t say for Chainlink because I don't know the tech but that’s pretty good for Polkadot vs OP

One thing about decentralization: Polkadot allows decentralization of collators but not mandatory, there are chains having the team operating all collators. While OP doesn’t give a choice, has to be a centralized sequencer.

On use cases: yes Polkadot allows smart contract execution through XCM in theory, but in practice it’s almost impossible to use trustlessly: without read access through XCM, you can pass only very simple calls