I see that there is an input element involved in dropdown for regular usage it is not needed/used. The one can add "readonly" attribute for that input. Should suppress keyboard popping up.
From a very VERY quick cursory glance I think the dropdown built by veutify employs an input element (possibly for the focusing and/or key typed selection) (IDK) but that is the thing that needs to be told not to pop out the on screen keyboard.
They may already have a way of specifying this in the v-dropdown (I havent looked). It may be possible via a class (at your end)
Thats all i have until i have more time I'm afraid. the Veutify discourse probably has this answered already.