I can say the same, but about single-player games. I play games very often (you can call me addict if you want), but every time i get to my PC i always get dragged into some coop/multiplayer game by my friends. While with deck, i can just drop to bed, fire up some game i've been delaying to play for 5 years, and finally complete it. Almost without distractions.
There is no web browser, Discord, Spotify, IRC or anything. Just you and a thousand games you promised yourself you'd finish some day =)
Also, on steamdeck subreddit i saw people using it as their main PC (not much power, but definitely more than enough for majority of day-to-day tasks, especially with external monitor). I recall motorola razr (android one) had dualboot (android + ubuntu), and when plugged to external monitor you was able to use it as a small PC. But due to pretty weak hardware back in 2011, this idea never took off.
A couple of times a year I think about whether I should ditch music streaming and pick up an old iPod