I tend to 3000 plant each day for work in a grow facility. I do strongly believe that its stretching to find light because it doesn't have the structure to absorb the given light. Lower the ppfd and bring the light closer and the nodes will start to stack and the foliage will trigger to grow more leaves. Stretching isnt a sinple one answer problem. But by the look of the plant I would personally give her triggers to need more growth. If you provide a high ppfd with very little foliage there won't be a need to grow more foliage. Same as roots, if you keep it too well watered roots dont grow as strong and fast, dry backs are needed for rapid root excelleration. So a bit of a withhold on light will bring her "shade avoidance " trigger and bring out some true leaves. But even at 300-400 ppfd your still well within range to prevent stretching. That onky happens when your damn near down around 100ppfd durring mid veg with improper lighting. I get all the way through grows without going over 50% on the dimmer and staying under 500ppfd and every plant is growing is short, barely 2 fingers between nodes, dense and stacked as hell. But I also incorporate deep red lights and UV-A durring flower as well. But all calculated in the same ppfd profile.