Generally, yes, for sleep. A paper book under a soft, warm lamp gives off almost no blue light and isn't full of the endless, stimulating content that keeps you scrolling. A phone is bright, blue-rich, and engineered to hold your attention, all of which can delay sleep.
If you prefer reading on a device, make it more like paper: use night/warm mode, lower the brightness, read a front-lit e-ink reader on its warmest setting if you have one, and consider amber glasses. But for the easiest wind-down, a physical book wins.
