Hello
@JappaWakka,
Apologies for the delayed update. As part of the 2.0 development works we have recently reworked our HUD textures, including the hotbar. We revisited your suggestion as part of this, and have unfortunately decided to change the previous decision to a decline. This is primarily due to the fact that players can change the controls allocated to selecting hotbar slots, meaning that numbering the hotbar would not make sense for everyone.
That said, if you're interested in our new HUD textures, you can see them in our 12th Anniversary Live Event recording here:
Thank you again for the suggestion, and have a great day!