I only use short finger gloves on/off road. I don’t need another thing on my body trapping even more heat (although a small amount). The dexterity is nice and I’m sure I’d notice it with long gloves, as I do in the winter.
I sunburn like nobodies business and always wear a cycling cap (no bill), and usually long sleeves and tons and tons of sunscreen. Have never thought to put it on my fingers and they’ve never burnt. I think due to their location on the bike they probably don’t get a lot of sun.