Support to more/new SIM cards

What is the barrier for supporting new SIM cards?

Primarily someone writing the code and continuously / actively maintaining the code.

AFAICT (and of course I’m biased), sysmocom is the only card vendor that has ever understood the value of open source tooling for SIM/USIM/ISIM/UICC cards. 99% of the pySim development and ongoing maintenance, documentation, etc. has been funded by sysmocom. And that despite the fact that 95% of said functionality is just generic, vendor-independent code implementing ETSI, 3GPP, GSMA, GlobalPlatform and other specifications.

sysmocom is doing this out of the strong belief in open source software, and also in the belief that many users will recognize this enormous investment in open source SIM card tooling and buy our products to continue allowing us to cross-subsidize this development from revenue generated by card sales.

So at the absolute very least I would expect that any other vendor caring about pySim support would at least actively submit and maintain code related to their cards, plus ideally also shoulder part of the burden of maintaining and further improving pySim in general.