Finding a good fit is easier said than done for probably most of us. Fortunately there are also new stretchy fabrics (including wool and denim) that give wonderful range of motion even when tightly fitted, or (in an unlucky situation) ill fitted. For example, you can find men’s slim fit jeans that look normal yet are flexible enough for even yoga or rock climbing.
Now that I found a brand that fits my build and uses this type of fabric, regular, non-stretch denim feels so constricting I avoid it entirely (and without, ahem, having to resort to men’s yoga pants).