Is this great primer on Ethereum 2.0 still up to date?

The Beacon Chain explainer you need to read first by Ethos.dev seems like a great primer on Eth 2.0. It is a bit out of date (it's from May 2020) and doesn't mention roll ups at all.

I've summarized it from this podcast readthrough from Ethereum Audible, would love to hear thoughts on how up to date this still is.

The basics of the beacon chain

Ethereum 2.0 is made up of two core aspects:

1. Proof of stake consensus
2. Sharding

While this primer is slightly outdated and missing the rollup centric roadmap for Ethereum it gives a great overview of the other two key aspects.

Beacon chain PoS

The Ethereum PoS is broken down into block slots and Epochs. Each block slot is several seconds long in which a validator is given the role of being a block proposer. Every 32 block slots compose one epoch. Finality of blocks occurs at the end of epochs.

The structure is as follows:

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• Each slot is 12 seconds
• An epoch is ~6.4 minutes
• Each block is verified and each slot epoch must receive 2/3 majority to be accepted as a legitimate checkpoint
• Once a checkpoint has been accepted it is ‘justified’ once the following checkpoint that links to it has been justified, the previously justified checkpoint becomes finalized.
• Finalization takes an average of 2.5 epochs = 14 minutes.

Sharding

One of the Beacon chains main roles is to coordinate shards. Sharding is a technique in database management. To grow a database you can either scale horizontally or vertically.

• Horizontal scaling means adding more power to each node.
• Vertical scaling means adding more nodes.

Sharding is a method of vertical scaling. While the current plans for Ethereum include 64 shards, it is clear as of the beginning of 2022 that at first there will be much fewer shards and they will not be complete Ethereum replicas, rather data storage ones.