All leather shrinks, to some degree. Naked leather is only made from the best hides, with the fewest blemishes. How much a jacket will shrink depends on the animal much more than any surface treatment. Lamb shrinks like crazy. Calf doesn't much, unless you hot soak it. Horse will shrink only a tiny bit, ime.
Bottega is very nice. The leather is terrific. It's actually so uniform that people who don't have much experience with leather goods mistake it for plastic, especially those pieces with a lacquered finish. The price is high compared to other companies, but if you want woven leather, it's the best in class.
I feel like we are addressing the issue. I do have jackets that are pretty constricting. However, if I sized up, I would feel that certain parts of the jacket wouldn't look right, and that would bother me much more than a bit of restricted movement, and constantly. I suppose if I couldn't actually lift my hand, that that might bother me more.
Comfort is more psychological than physical. I feel more constricted in soft cashmere than in a leather jacket and heavy denim. Some others feel comfortable in a suit and tie. If physical comfort was the key, then we'd all just wear sweats.