When I place the S10+ next to the Pixel 3XL they appear to be the same physical size so I'm not sure you mean by the Pixel being embarrassingly large.
Galaxy S10+ is smaller in every dimension (LxWxH) than the Pixel 3 XL and has a larger screen, substantially larger battery, more cameras and 3.5mm jack. With all those features/specs in a phone that has a larger screen in a smaller body, yes the Pixel 3 XL looks Embarrassingly large to me.
The Galaxy S10+ is a good 2-3mm thinner in width as well, which helps tremendously with one hand usage.