The only thing that comes to mind is battery damage. Keeping your laptop constantly plugged in and heating up during intensive work / gaming sessions will speed up the rate at which the battery ages. However, it's a Framework, so repairs are reasonably cheap and doable - so even this point has shakey ground to stand on.

Aside from that - there is no loss. I, too, use my laptop as a desktop replacement with a dock nowadays. Laptops have gotten so good that while surely desktops are still better, many users - even heavy ones - are fine with the performance output that laptops give you.