Turn off HDMI and USB ports

Hi!

Have been looking into doing small reductions in power consumption on my raspberry pi 4 hosting HA,
however I cannot see any previous post on how to circumvent the read-only restrictions and disable HDMI or USB. From a few of the posts I have seen I get the feeling HDMI is already disabled (is it tied with HDMI CEC being turned off/removed?).

Cheers and thanks for any provided help or pointers.

Still looking, I found that USB is generally unadvisable due to sharing the same chip with bluetooth. But noone seems to know except for debugging if HDMI is necessary or how to turn it off?
/X

This may be outside the scope of homeassistant os, but may be achieved running it on top of pi os or Ubuntu.

With that said, the power gains are likely to be extremely small.

Yes, it is something I have tried, but the host seems minimal and many tools are non-existant. Besides, it seems RPi4 has moved away from many video tools as well and onto more generic ubuntu tools.
Either way it would still be nice to find a work-around.