You can now turn your Raspberry Pi 5 into a proper retro gaming PC with official hardware as the manufacturer just released its own PCIe 3.0 SSDs

uses the Arm A76 cores, ao the smartphone SOC to compare it to would be ones using the Snapdragon 855 (e.g Samsung S10) but neuter its multicore perf becauae mobile uses both big and little cores.

tldr will run some games, but not all. still struggle street

Box86/64 and FEX can both run Steam on ARM. Lighter games should be playable on RPi4 and 5.