[delayed]

That's actually a very good point, I haven't seen any care for power consumption from software developers in many many years. The only people who seem to still care about it are hardware developers like Valve and Apple.

I figure that doing less work generally requires less power, but some developers are crazy and act like they own the whole CPU, generate tons of heat, stress out the cooling system etc. with multithreaded bullshit when they did NOT need to be multithreaded.

Not sure why multi threading is a victim. It really depends.

It does indeed depend.

Some multithreaded workloads will use the full logical processor count to pin every core and that can really suck on low-end systems. I think aside from balancing multithreading overhead, this is one of the reasons why some more advanced software (such as 7-Zip) lets you select the number of threads to use for a workload, even if you already know and accept that it'll be expensive until it's completed.

Lots of multithreading things I come across as a developer have a default of something like 4 threads, or only use a certain fraction of logical cores up to a certain maximum, etc. because it's generally more polite not to always pin every core.

Depending on what you're doing GPU accelerated rendering is more battery friendly than CPU rendering though.

Drawing the entire interface is more expensive than drawing only what changed, though. You don't have to give up the GPU for that.