hello. I am trying to maximize the volumetric flow of city water coming out of the city pipe on the right side of the picture. That's 1/2 inch PVC. It's my "theory" that the black T-joint circled next acts like a flow reducer, but I have no evidence (I'm not a plumber). Also, I bought a "high flow" spigot to replace that narrow one you see on the left, but i cannot even unscrew that adaptor from the PVC. It just spins and spins. Should i have someone replumb this short circuit, presuming that getting rid of that black T-joint and using a high flow spigot will increase the volumetric flow?

Hoping for expert advice here