AGI I personally find Iris more advanced, for example, it can auto change your blue light value based on time of day/night in where you live in by using approximation (basically taking the city/country you live in), while flux is only locked to the position of the sun and uses geolocation which takes your exact coordinates and feels like a privacy issue for me.
It has locked blue light values, with Iris you have full control 0K-6500K and you can choose
Iris has Types, which are like presets made from us. We have Health (general usage), Sleep, Programming, etc. You can also invert the screen and have dark mode on whatever you want
We actually have an article on this, you can check it here:
https://iristech.co/best-alternative-to-f-lux/?ap_id=pernichev_quora