Which calls to Tornado Cash Smart Contract are blocked by Infura and Alchemy?

Hello. There are various news (I'm sure you heard of) which say that Infura and also Alchemy block calls to Tornado Cash due to sanctions.

I created accounts on those platforms and tested a call (uint256 denomination()) to the Tornado Cash Smart Contract (I hope 0x910Cbd523D972eb0a6f4cAe4618aD62622b39DbF is right, there). Alchemy, Infura and testwise my own node did reply the same output.

So either those platforms don't block calls to Tornado Cash smart contract OR they are just blocking specific (other) calls. (Or, even worse, I did address the wrong smart contract.)

Can someone clarify what exactly is blocked by Infura and Alchemy? Or did they only cancel the subscription(s) of Tornado Cash?