There’s no such thing as a desktop 1650 Ti, so with 4GB of VRAM I’m assuming it’s a slightly beefed up 1650. Laptop components are generally much less powerful than their desktop counterparts despite the same naming schemes. But anyway yes, you should be getting more though it depends on the circumstances of your ride and your setup. If this was in a group event or with a busy pace partner then frame rate is always much lower than normal.
In any case, check you’re plugged into the mains, that you’re on the High Performance power plan (and any other sliders are on maximum power), and that the power setting in the Zwift menu is set to battery saver off. Are you absolutely sure Zwift is using the GPU and not the i7 for graphics? Put a log file into Zwiftalizer to be sure.