I have an xfx rx 6650 xt which consumes a maximum of 50 watts on 100% usage. This does not seem normal to me. I have tried different programmes/games and tested that the wattage is correct.
I tested my old rx 580 8gb running at 120/150 watts. But is it normal for this card to run at this wattage?
100% usage does not mean it will consume more but you haven't gave us much info to start with.
I would start a serious stress test for your GPU and log the results.
Let me give you an example.
You said that your old RX580 had 120/150Watts. My RX480 spiked at 210 W and was normally around 180W. At first sight that would look strange, don't you agree?
How much FPS are you getting in gaming? Have you compared online?