The entire point of having multiple ciphers is that some will break.

Did the world end with any previous one breaking?

It’s incredible and awesome if AES GCM has a flaw found with an AI now, Chacha20 could be a direct or nearly-direct replacement.

The sooner a cipher breaks, the better.

Sure, but in an era where major unsolved mathematics problems start getting knocked out one by one, what if attacks for all of them are identified in the space of a couple of years?

I don’t doubt that we could come up with new crypto algorithms equally as fast, but how do you trust that they are resilient (or even just implemented correctly) without an extended vetting period?