I have my bookmarksbar setting in Orion set to text only.
When I open Orion, it shows only text.
When I visit some websites, after a while it starts showing icons and truncates text.
That the setting is honoured.
Orion, OS version; hardware type:
Orion: Version 0.99.122-beta (WebKit 6188.8.131.52)
HW: Macbook Pro M1Max 16"