This reminds me a lot of Freakonomics podcast episode (https://freakonomics.com/2010/02/06/the-dangers-of-safety-fu...) where they discuss different cases where increased safety measures just encouraged people to take more risk, resulting in the same or even increased numbers of accidents happening. A good example is that as football helmets have gotten more protective, players have started hitting harder and leading with their head more.
Devs have been given better baseline performance for free based on internet speeds, and adjust their thinking around writing software quickly vs. performantly accordingly, so we stay in one place from an overall performance standpoint.
This is known as Jevons paradox in economics and the classic example in modern times is rates of total electricity usage going up while devices have become ever more energy efficient.
In the case of devs it's not just staying in the same place though. You get more complete frameworks, more analytics, better ad engines, and faster development pace.
It might not be what we wanted, but it is a benefit
Devs have been given better baseline performance for free based on internet speeds, and adjust their thinking around writing software quickly vs. performantly accordingly, so we stay in one place from an overall performance standpoint.