Computers are not getting better at the rate they used to, but we are still improving both on performance and power.

However, the largest change we have seen the last couple of years is the accessibility of computer power. These days an attacker can be concerned mostly by how many CPU/GPU hours he needs to rent from Amazon or equivalent providers to achieve his goal. So the accessibility, convenience, and price of processing power is still improving quite fast.

Depending on your interpretation. If you go by the relatively useless transistor/fixed price cpu then it is dead, but if you go by more practical measures like instructions per second in whole system/dollar the it is as fast as ever. GPUs are really fast and still advancing.

Moore's law is, but the cost of a given amount of computational ability is still going down quickly.