Excellent post and thank you for the mention.

Here is my feedback:

Every interaction you have with the blockchain involves requests to it ...

It is important to distinguish between requests (reading data from the blockchain) and transactions (storing new data on the blockchain). The first one is completely free and does not require RC, only the second one requires RC.

By generating an overwhelming number of requests, they could significantly slow down the entire blockchain or, worse, temporarily "take it down."

Given what is defined above, this is not possible. Requests are addressed to public API nodes, which could have difficulty responding to an overload, but it would be necessary to attack all API nodes simultaneously to block access (meaning reading) from the blockchain.

Again, this is only valid for those who rely on a public API node. Nothing prevents you from running private nodes.

Therefore, to take down the blockchain you need to take down the internet.

RC is the mechanism that makes the network resilient to such attacks

This is not correct. RC is what gives a cost to the recording of transactions, even if it is not (directly) financial.

RC prevents an actor (using one or multiple accounts) from spamming the blockchain for free, filling blocks with transactions to prevent others from recording their transactions. In no case will this slow down the blockchain, which will continue to function normally but will delay excess transactions. But from a user experience perspective, there will indeed be a feeling of slowdown.