Example pic isn't supporting the argument much. Out of the 5 boats, one has fwds pointed mount, one straight, one mounted (looks like) on the roof, and the one in the back, bit difficult to see but looks straight, or on a frame. One has no radar at all.
Not seen a "preference" for forwards pointing in UK boats anyway, strange I did wonder also why in some pics why lobsterboat models had a backwards and bent pole for the steaming light, rather than just straight up. Fashion maybe??
...Apologies, I "quoted" the relevant pic. but the forum seems to remove the image. Tried 2 or 3 times to correct so you'll have to remember the pic I'm refering to above.