I realised that the PS5 has on the front
1 USB C port, and 1 dedicated charging port (USB A) without USB function.
"USB Battery Charging defines a charging port, which may be a charging downstream port (CDP), with data, or a dedicated charging port (DCP) without data. Dedicated charging ports can be found on USB power adapters to run attached devices and battery packs. Charging ports on a host with both kinds will be labelled."
What this means is that if you plug in an arcade stick into that USB-A port, it won't function (I wouldn't be surprised if they kept the USB-A port to charge DualShock 4s, since they apparently work on the PS5). That being said, I'd imagine that there will be back ports as well. But given that Sony made the USB-A front port only for charging, I wouldn't be surprised if the back ports that are for data end up being USB-C.
Source: Sony (pointed out by EagleClaw here on ResetEra)