Quoting: SnipeRV
I think you might be confused on the value of a late first round draft pick. Fabbro is a guy who can be SERVICABLE as a top pairing RD. He's not great, but not terrible. He's a solid passer and decent on the rush but sometimes makes mistakes he shouldn't. He's just now entering his prime and he's an RFA. Your late first rounder statistically won't play more than 100 NHL games. So, to be honest, Fabbro is likely worth more than that.
No, I'm definitely not confused about the value of the 1st. I'm looking at established precedent and finding that the only Dmen that typically go for 1sts are of a higher established quality- typically with a more standout ability- or are younger, high-potential pickups. Recent examples are as follows:
Sandin (at age 22) went for a 1st & Gustafsson (higher offensive ceiling & younger)
Ekholm+ went for a 1st, Barrie, & Schaefer+ (top pairing stud)
Hronek+ went for a 1st & a 2nd (higher end offense)
Lundkvist (at age 21) went for a 1st+ (likely comparable, but younger)
Romanov+ (at age 22) went for a 1st (perceived higher ceiling but, whether accurate or not, still younger)
Even if we go further back to an oft-cited trade used to justify inappropriate valuations, Chiarot for a 1st+, Chiarot was exactly the right kind of Dman that's highly valued by many GMs in the playoffs and was coming off a long postseason run in a top pairing role w/ MTL. What you're pointing at and demanding a 1st for has none of these qualities. He's 25, doesn't play big minutes (currently only plays 3rd pairing mins by amount), doesn't do any one thing exceptionally well, isn't big, and apparently his skating holds him back (I'm assuming that doesn't mean he's awful, just around average). Literally nothing about him suggests he's a.) worth a 1st compared to the typical trade market or b.) that he's an upgrade on Ceci (which isn't your point but that of the author of this thread).