Thank you very much for the answers
@Moukee
Do you know by chance if it also works with a docking station of some kind (that has an external drive) in between the iPad and Monitor?
Most USB-C hubs/docks should work fine. Just keep in mind that docking stations
requiring Thunderbolt won't work and DisplayLink docks won't work (for display output at least) because there's no DisplayLink driver for iPadOS.
As an example I have an HP Z27q G3 monitor with USB-C, and my iPhone 16 Pro happily mirrors its display to the 4K screen (scaled, obviously), the keyboard I attached via USB works, as does the microphone and headphones (also via USB). Even ethernet works. Just the mouse doesn't, but it should work under iPadOS.
You can get cheap USB-C hubs from Anker or similar brands and they'll likely just work.
EDIT: And yeah, most USB drives should also work fine. As for docks with an SSD built-in, you'll have to check the specs, because it'll likely not work if the PCIe lanes from the (NVMe) SSD are just forwarded, as that would require Thunderbolt.