It’s still emulation. Yes, it’s emulating hardware, as close as possible and often indistinguishably close, but it’s still emulation.
For example, my EDGB X7 runs fine on any real Game Boy I have, but can’t switch games on an Analogue Pocket.
Another weird issue that I had was that if I launched my Pokemon Crystal save on Pocket it would, for some reason, permanently change my character from a boy into a girl (without saving the game!). This wasn’t happening on my Game Boys (I restored the save a couple of times to test it).