Q-day is coming. Encryption will most likely be broken within 5 years with quantum computers. Possibly sooner if we extrapolate accelerating advancements. This means old addresses will be up for the grabs. This means Bitcoin becomes unsecure. Big money knows this. Yet they still push this past $100k. Quantum resistant hard fork won't be easy or smooth to implement.

The usual argument "B-b-but banks will be insecure, too!"

Not quite. For banks and centralized entities it will be way easier to implement additional safeguards and transfer to post-quantum cryptography. For decentralized cryptocurrency - not quite so.