They don't even decouple at high material standards of living. Recent increases to GDP produced emissions too but those new emissions were offset by reductions in emissions of existing industries.
This "decoupling" gets us basically nothing because it's not like we can just stop emissions tomorrow since GDP and emissions are "decoupled".
Counter example: if we can make computation 1000x more efficient per teraflop, we could use computers to trivially design drugs to cure cancer etc (just a random example) and yet our energy consumption would not change. GDP may be the wrong measure, but there would be economic growth or standard of living growth for no change in energy consumption.
An Apple Watch has more processing power than a Cray 2, but it uses a rechargeable battery instead of a 150kW power supply.
The problem is that cycles expand to fill the space available, so another 1000X drop in efficiency would mean new kinds of applications rather than being limited to affordable super computing.
While individual computers are far more powerful and use far less energy, the power consumed by computing on Earth as a whole is far higher than it was. (Not even counting energy vampires like crypto.)
There's no reason to assume that trend would stop. Displays could easily have much higher resolutions (possibly holographic), IOT could be truly ubiquitous, AI could be in everything, entertainment could be social, interactive, and immersive, and so on.
> if we can make computation 1000x more efficient per teraflop, we could use computers yo trivially design new drugs to cure cancer etc
You're assuming two things: that cancer and disease can be cured by any feasible increase in computing power (not that outrageous an assumption), and that the energy savings won't be offset by keeping an even older population of disease survivors comfortable and alive. Reality is not as simple as "cure all our ailments and we're good to go".
