I'm trying to understand the reasoning as to why a contract like (https://etherscan.io/tx/0xcdbff8c3535e2f336be07ae63420733d23a6dca9d859147a65488c0a995599a2) would want to do so many self transactions (and pay gas each time)
It is most likely a transaction that cancels another one.
You can cancel a transaction by sending another transaction from the same address with the same nonce, with a gas price at least 10% greater than the gas price of the cancelled transaction.
If you want to reduce the gas cost of your cancelling transaction to the minimum, making a transfer to yourself would work because it only uses 21000 gas.
The most useful case I can think of is stacking transactions in the block to displace other transactions in the mempool (you may notice that fees are actually higher than usual today for simple ETH transfer). It could be some kind of attack as well as just a form of protest from a miner, for example against the EIP-1559 as it was pretty hype recently, but it is really hard to say exactly.