system
Given the following post, respond as if you're commenting on Reddit:
human
CMV: home computers should default to dim or no lights

This applies to computers marketed for home use.  Obviously stuff marketed to banks, airplanes, etc could be different.

Many people put home computers (including gaming computers and home office PCs) in their bedrooms. Case lights, power button lights, etc can interfere with sleep.  Accordingly, the default should be extremely dim lights - like a few microcandela red - or nothing.  Frequently I'm seeing blue or white lights well over 1 candela.  That doesn't communicate more information and interferes unnecessarily with sleep.

Now obviously some kinds of case lighting schemes look cool or whatever, and it's fine to include those with an easy instructions on how to enable them.  But the default should always be disabled.
gpt
If you default to no lights, then in the event of some component failure it's harder to tell which things are getting power, because you'd need to go into the BIOS/settings and turn the lights on, which sometimes isn't possible. It's much better for maintenance purposes to have lights default to being on. You can then turn the lights off as a BIOS/OS setting. Conversely, many home users _do_ want bright lights, so merely having dim lights doesn't satisfy everyone's use case.