Its a "fundamental principle" of the Bitcoin community yes, its strongly held as one of our core tenets. But it could still be changed. So stop saying its limited without pointing out what its limited by.
Well I would like to also point out that if the 21 million cap limit was increased then what we have is no longer Bitcoin.
Even if 99.97% of the users still call it "Bitcoin" it won't be Bitcoin to me. It would be a PoS coin. Not proof-of-stake, but piece-of-shit.
Same for me. The rules were set in stone, anything that raises the total amount of coins is a scam and not Bitcoin. Show me proof of Bitcoin having problems to survive long term without inflation because there's no sound proof to be found out there. The inflation will be so small by 2040 that you can consider all coins mined already, most of the revenue will be fees. Hell in just 10 years the curve starts becoming incredibly steep which is another reason why I think by 2027 the price will be 6 figures to a million dollars (assuming big block retards don't ruin it with wanting to hardfork everyday):

Notice how there is a big change in angle in 10 years. In 2040 you can consider bitcoin 99% mined.