Bitcoin is NOT mathematically limited to twenty one million bitcoins.
I do not support raising the cap at this time but if we had overwhelming support like we did for Segwit we could raise the limit to any number we could dream up.
I would have no issue changing the code to allow a 1 bitcoin reward for every block forever... to ensure a strong distributed mining community.
I understand this must sound like blasphemy to the majority of the community but it irks me to see such a false statement about bitcoin repeated over and over again in every Bitcoin youtube video out there; there has to be a better way to phase it.
The whole point of Bitcoin is that it has a limited supply. Some bad actors want to increase the total supply in the process (Bitcoin Unlimited would need that) but some people like Tone Vays which are known for their anti hardfork policy, have questioned if Bitcoin is viable forever with 0% inflation.
Im yet to see clear evidence of BTC not being viable with a limited supply forever. The fees derived from the transactions should be enough to incentivize miners to process the transactions, or at least that was Satoshi's original plan.