Not sure about the GPU, but I have noticed the CPU using unreasonable amounts of power, too, for trivial things. I guess some microcode deciding it’s a priority to boost as high as it can for a specific task when in reality 10W would’ve sufficed.
I initially set out to fix that firmware bug myself but after realising I don’t WANT more than 30W (since the performance is largely the same) I dropped that. I just don’t trust the CPU governor to use it’s power sparingly and only when appropriate.