It's a lot of money tied up into a depreciating asset

That's such a weird take. You already bought and enjoyed a machine most people would consider way too expensive "just for coffee". Which means it's a passion buy, not an utilitarian one. Especially since you, quote, "are not hurting financially". Depreciating assets are for commodities, not passions and hobbies. Otherwise, what's the point in life? Selling it would be a net loss anyways, because at some point in life, you might want to buy another one and you'd lose the depreciation on this one plus inflation.

Don't sell or you'll regret it. Kids grow up quick, you'll find the time again to appreciate a nice espresso very soon. Get a cheap alternative for guests and/or inconvenient times. Keep the nice espresso machine.