Its not just NHL series, a lot of online games have gone the route of Engagement Optimized Matchmaking over Skill-based Matchmaking. My guess is the numbers somewhere confirm more player engagement using EOMM over SBMM. At a macro level though it can get pretty frustrating. My team takes on whoever we are matched with and occasionally its lead to some great moments of overcoming higher ranked teams with careful gameplay. More often than not though its usually we hang in for a bit only to get stomped once the **bleep** breaks and we quit. Hopelessness creeps into a number of our members.
If the wait time would really be as bad as Aljo indicates, I would prefer instead of locking a matchmaking search to specific lobby size/skill, start with the desired attributes and then expand the search circle every 30 seconds until you have a match. Many other online games actively tell you during matchmaking when a desired match isn't found and they are expanding the search.