Fake hashrate wouldn’t explain the six block reorg. Although they didn’t have 51%, like some media organizations with low journalistic standards might have claimed, they did have enough to cause some serious disruption for a short while.

It’s not impossible to do a similar attack on Bitcoin, but having millions of ASICs securing the network makes it more resilient against external bad actors who can’t just acquire such a significant share of hashpower overnight. In theory, a big pool like Foundry, might be able to do this kind of attack, but in practical terms it would be very difficult because individual miners would defect to other pools and the financial damage would be devastating. It would be counterproductive and illogical to attack the network that your multi-billion dollar business relies upon.