External USB keyboard connection on USB issue

Engineering compatibility with multiple standards is always more challenging and more expensive. If a fixed selling price is their primary goal, you get less flexibility. It is economics 101. It seems like this should be a familiar principle. Did you miss this one?

The commonest reason for functional problems on simple USB devices is voltage drop due to thin wiring.

As a guess, you are not connecting it directly to a port on the motherboard, but via a case connector or extension cable??

USB3 case adapter cables are usually much better made with higher current ratings, so less likely to have such problems.

There's no good reason why it should fail.

It is not likely to exceed power and speed is backwards compatible.