I think they look a bit bigger but you need to do more for them. You don't train them hard enough with enough volume. You need to squat, lunge.
Without knowing dick about the person in the pics, my first suggestion would be to ditch any focus on the weight being used for whatever you are doing for legs. Then pick 3 compound exercises for your legs (quads and hams combined) and focus on those 3 movements for a month. My suggestion would be squats, stiff deads, and leg press. For each of these I would concentrate on the fully stretched portion of the movement. For squats, that means going down to where your ass touches your lower calf. For stiff deads, that is you touching your toes. For leg press, that is your knees touching your front delts.
You've obviously trained regularly so you have a base of muscle but think of it as re-learning and connecting with the stretched portion of the movement (most often neglected). I would say 5 sets of each. I would say 1 count on the up, 3-4 count on the down, 2 second pause in the stretch (not resting at the bottom but stretched under tension) and no resting at the top of the rep. For the first set of each I would use no weight but get used to the movement going to 25 reps. Then for squats I would go up a quarter on each side per set (I know it isn't a lot, trust me). For stiffs, I'd go up a ten each side each set. For leg press I'd go up a plate each side each set.
Afterward, I would do one set of bodyweight walking lunges from one side of the gym to the other.
In my opinion, the most likely thing holding back your leg progression is you range of motion.
Good luck. Hope it works.
