I don't think we will make any minimal linux distro with only RPCS3 built-in.
User would still graphic ambient to update drivers and the emulator itself regularly, and perhaps to copy new games to RPCS3 folders instead of using shell commands.
We don't emulate XMB, so there's no way to "boot up like a normal PS3" for now.
Desktop: Ryzen 7 5800X, Radeon RX 6800 XT, 2x8G DDR4 3600MHz, Manjaro Linux
Laptop: Ryzen 9 5900HX, Radeon RX 6700M, 2x8G DDR4 3200MHz, Manjaro Linux
Old Desktop: AMD FX-8350, Radeon R9 280X, 2x4G DDR3 1600MHz, Manjaro Linux