At which point, they don't need digital devices. Take the time and effort you'd spend on that and buy them legos or something age-suitable, and keep them in the physical world as long as you possibly can.
My kid has a tablet, but we limit the amount of time he spends on it. Seems healthy to me.
If it's anything with touch screens, it's designed to be so easy that you don't have to worry about it. They'll pick it up trivially later in life.
If it's how to use a keyboard, mouse, and Linux shell? Have at it. I've met more than a few 8-10 year olds who literally don't know how to use a mouse, because everything they've ever interacted with is touch screen.
But I'll take "a kid who played with legos and outside a lot" over "a kid who was electronically literate" any day.
But I do want to build some level of digital literacy, and most importantly just make sure they learn how to type properly when the time comes. Hence the question, I want to introduce them to tech with extreme caution.