This driver was merged back in 2020 and now with pending driver patches is being extended to also cover Alienware systems. With being owned by Dell, modern Alienware systems are quite similar to those branded as Dell. In the case of the dell-wmi-sysman driver it's just a matter of adding OEM string checks for "Alienware" to complement the Dell checks.
With these patches adjusting the checks to accommodate for Alienware, these modern gaming-focused systems should now be able to enjoy BIOS management under Linux with this driver. The patches are still being reviewed but hopefully will be ready by the next kernel merge window.