Not sure about SIM cards but you can still use cash to buy prepaid phones along with an amount of minutes/text to activate. Like the kind of prepaid phones that you you see the vendors sell x minutes/text/data. e.g. I’ve never been asked for a credit card to buy a Tracfone. Some places like Best Buy will ask you for other information to sell it but none of it needs to be real (ironically Best Buy asks for a phone number to buy a prepaid phone, LOL). You do need to set up a Tracfone account online to actually activate a phone + plan, not sure about the other prepaid vendors.
IPFS by default isn’t set up to work around censorship or anything of the sort. Protocol Labs (creator/maintainer of IPFS and Filecoin) have always honored copyright takedowns, etc. on their own infrastructure and have done a fair amount of work on content blocking within the default IPFS clients and such.
e.g. https://blog.ipfs.tech/2023-content-blocking-for-the-ipfs-stack