And nobody can change the programming? You have seen the source code?
Any attempt to change the programming would be instantly rejected by the thousands of independent miners on the network whose purpose is to ensure that all transactions are valid. It would render it almost impossible to successfully implement such a change. It would require an enormous collaboration by everyone involved with bitcoin. The entire system is set up with the purpose being that no one person or small group of people can change anything about it.
https://river.com/learn/can-bitcoins-hard-cap-of-21-million-be-changed/#bitcoins-hard-cap