Welcome! This forum has a treasure trove of great info – Scouters helping Scouters! Just a heads up, though - all content, information, and opinions shared on this forum are those of the author, not the BSA.
I think parents should still be able to, especially in the case of a troop that doesn’t actively use this feature. Parents are prevented from marking it approved, though.
I understand historically when Scoutbook was first expanded to be used by troops it was based on a program written to support packs.
Let us remember that Scoutbook needs to support different types of units with different leadership organizations.
Troops are not packs. The youth performance standard in a troop does not include the parent doing the work a Scout should be doing. The Scouts are expected to be leaders and parents are not expected to do the work for the Scout.