I've just bought a pair of black, bootcut jeans. Like you, I think they are easy to smarten up, with a blazer and heels. In some offices, they would pass as smart casual workwear. I think they have made a bit of a comeback. Skinnies are still everywhere, despite last year everyone saying they were OVER and you may as well burn them all now to save yourself embarrassment 😂.
I like having a few options in my wardrobe for jeans, as I wear them most days. I still have some skinnies, but also have bootcut and girlfriend.