The statistical likelihood of a 51% attack happening on the blockchain seems statistically way less likely than a hack targeting our existing financial system.

I mean, it's pretty easy why blockchains are considered immutable, you can even code one from scratch in Python in less than 200 lines of code.

To control 51% of all those hashing power, an entity would need to power computers that works as much as that, along with paying for the equipment and energy consumption and whatever costs needed for the operation. Current estimates of Bitcoin mining energy usage stands at 71 TeraWatthour, enough to power the whole country of Austria.