XP has vbscript in the command line, giving you more processing power than a standard calculator... Not that people would have time to code, but maybe there could be an advantage to be had. A custom Linux build would be easier to lock down, I think.

That's what human proctors/supervisors are there for at exams.

Exams problems are designed to make use of only basic scientific calculator features, I doubt you have the need, or the time, to start sneakily writing VB scripts to try to gain an edge, while the proctors are not looking.

If someone is using Windows XP in any official capacity in 2023 they should be summarily terminated for gross negligence and sued for damages.

It was an example of how exams that required calculation aids were in my school back in late 2000s. Feel free to adapt it to modern days but the concept stays the same.