It’s been awhile since I’ve noticed this honestly, probably around the time they refactored the library & different views for your games but I realized that those annoying self-updating client packages that would restart steam seem to be a thing of the past. I was looking through my download history and the thought occurred to me that Steam hasnt forced a restart on me in so long.
For those who don’t know what I’m talking about, it would be a popup like this that would come up 5-10 minutes after steam was running. 
I’ve seen the same thing. Seems like the new behavior is to just let me login, play, and it will get what it needs in the background and automatically update on next launch.
Makes sense not to bother me to update a 0.1 release change after launch (unless it’s urgent) when I just want to play Tetris.
Isn’t this the same behavior web browsers use? Background download and update on next launch?
Not complaining, I prefer this update cycle as default.