I'd wager these produce less oxygen in part due to the glowing aspect. Photosynthesis is mostly only active during the day when there's enough photo to help synthesise carbon dioxide into oxygen, glucose, and starch. During the night plants switch over to cellular respiration where they take their stored energy (glucose), and burn it, converting oxygen to carbon dioxide and water.

I'm guessing producing the light will require some amount of energy so the general net gain/loss in terms of oxygen is probably affected. On a global, or even national scale I don't think the oxygen production of deocrative plants in cities will matter much.

Love the idea of glowing plants. Very fantasy.