Starch converts to sugar in the human body. Sugar provides no nutrients, but does decay teeth and bones. Hundreds of digs show decayed teeth and bones after agriculture, and none before.

There is no chance humans would have searched for and dug up plants to eat, especially when there is no nutrient value in doing so, and most modern plants did not exist then.

OTOH, animals to kill were plentiful.

The sources you cite all seem to have a pro-veggie agenda. They weren't archeologists looking through a dig with an unbiased view. They were specifically looking for things they could claim were fragments of veggies.

Not persuasive, compared with all the other digs that have not shown this.