I understand the title of this thread. The new ARM-based Macs run either the exact same SoC or a derivative (with more cores, memory lanes, etc.), so I think these arguments apply verbatim to ARM-based Macs. If anything, the emulation of the x86-64 ISA via Rosetta 2 will create additional overhead.
Plus, this is also an issue on Intel-based Macs with slower and less efficient CPUs.
Have you had a look at TR’s Mac app? 
It doesn’t conform to any Mac UI conventions … in fact, I can’t use it, it’s so bad.
There are lots and lots of smaller issues with regards to battery life and efficiency, not all of them are CPU-related. For example, some Macs and iPads have variable display refresh rates. Lower refresh rates mean you can save energy as both, the GPU and the display will need less power.
This was an issue on the Mac with many apps that “fixed” to a higher, less energy-efficient refresh rate — including Chrome (not sure this is still true). It stands to reason that Chromium also is not aware of this (Safari is, though), which could sap additional energy.