Diana, I agree that seamstresses weren't necessarily all skilled back then, but the pockets on bags I've seen in older bags are sewn using different techniques (not top stitched like this one) and not with a contrasting thread! That looks very amateurish, it's only the modern sewer who would be happy to leave it like this, especially with the beautiful beadwork.
It would be easier if we knew what the fabrics were - eg, are the beads plastic or glass - obviously '20s beads will not be plastic - is the lining cotton, is the braid cotton, silk or polyester? A modern braid would probably have some synthetics.
I agree with the others, and stand by my earlier assessment that this is a remodelled piece, perhaps with '20s elements but on the available information I can not support the idea that it is "mostly '20s" although, as with all identification enquiries posted here, looking at photos and asking questions are never a substitute for holding it in your hand.