It looks like this is "by design", in the 2D Script the sizes are hard coded with comments like "! NCS standard 1/4" (6.35) 6 by design". You can try the Identification Label 19 which has shape and size options (Custom Settings > Label Geometry), but only if the pointer is not activated.
David
David Maudlin / Architect www.davidmaudlin.com Digital Architecture AC27 USA • iMac 27" 4.0GHz Quad-core i7 OSX11 | 24 gb ram • MacBook Pro M3 Pro | 36 gb ram OSX14