To be honest, I don't know who buys these portable monitor. Any cheap Dell 24" (I use an old 2414h but newer are the same) for ~250€ will do. They detach from the stand using a button press (Dells proprietary mount system), have almost no bezel, and are relatively flat to fit into a suitcase or even backpack. I use an Osprey 80l travel backpack, and that 24" screen is easily placed at the very back of the backpack.
I even sometimes use a bigger suitcase with wheels, I can fit 2 screens in that suitcase easily and use a Dell MDS19 stand - the pro for this stand is, you can unscrew the bottom (no screwdriver needed!) and it is just a very thin flat piece. The other part is also basically just a long heavy bar with the monitor mounts, but in total it is easier than to transport the two individual stands.