"Waste of time" has to account for all the side-effects. Once the glue
sets, the glue should be stronger than the wood, so no other fasteners
are needed. But... did the dowels help you assemble it? Did they
maintain alignment for you? I use biscuits for all my glue-ups, despite
trusting the glue, because overall they're worth the effort.

So no, I don't think they're a waste of time.