If they FBI did actually crack a private key, it would almost certainly have to be with a top secret, insanely powerful quantum computer that's decades ahead of what is publicly known to exist. The existence of such a computer that could crack bitcoin private keys would also be a powerful tool against every organization on the planet and their ability to maintain secrets.

I'm referring for post quantum cryptography, https://en.wikipedia.org/wiki/Post-quantum_cryptography, which would negate the usefulness of such a quantum computer at cracking competitor secrets.

Bottom line, there are much more useful things you could use this computer for, like cracking all encrypted communications of a foreign power or hacking into their military or financial systems. Using it to crack a single bitcoin key to recover a few million dollars only serves to alert all your adversaries that it's time to upgrade their cryptography.

I believe he's talking about encryption algorithms that are safe from quantum computers

I don't understand the question.

Who decided that we needed to migrate to HTTPs everywhere? Or that authentication for online bank accounts needed to be encrypted?

As cracking of traditional encryption becomes an obvious problem, systems will be upgraded or people will vote with their feet.