I still use flux since I prefer to filter out some blue light during the day, keeping it around 5500K.

Flux helps just with one part. Relax in evening due to removal of blue light. But second part is, that in morning and during day, you really should see blue/full spectrum and intensive light. Either by going outside, or you can buy some light therapy lamp that provides you with this (when natural light is impossible). I do not think it's good idea to deprive yourself of blue light whole day.

Not to rain on your parade but get a colorimeter and check your screen I’ve used my xrite i1 pro and the amount of blue light doesn’t actually change that much when you switch your white point temperature to warmer settings and especially when it’s as high as 5500K.

MacOS, Windows 10, and Gnome 3 all have a night mode now.

iOS supports it as well - actually there was a controversy when Apple removed f.lux from the app store and then rolled out its own similar feature if I recall correctly.

Orthogonal to your point, but f.lux was never in the App Store because it had to use a private API to pull it off. They did offer it as an Xcode project for a while, IIRC.

It's called Night Shift on OSX and it's also builtin