The show has the right amount of pacing IMHO. It is masterfully done.
It starts off slow as that's sort of a key part of it. There is a lot unfolding over the course of the season.
I can't recall any part of season 1 as boring TBH. Pay attention to the small details and the interconnected loops and what they may reveal. You'll be very engaged even during the slower portions.
I completely agree! But I also find a lot of people I know consider shows of this type "too slow/boring" to keep their attention very long. I feel like this is more a fault of modern society encouraging everything to be instant-gratification and constant stimulation. (And by modern society, I'm referring to the way things seemed to go by the 1980's, when many of us were growing up and consuming media content in large quantities.) Severance is the type of show that requires your undivided attention and noting the details to get the most out of it. People who multi-task watching a show with doing other things aren't going to get a full appreciation of this one.
I just started re-watching Severance because I wanted my g/f to see it. Watching it together, I realize how even episode 2 continued that fairly slow pace where they put some time into wanting you to digest some of the cinematic details or even "Easter eggs". (EG. Inordinately large amount of camera time spent just looking at Lumen's parking lot in the snow, where those paying enough attention will admire the way the snow creates severed rows of parking spaces.)