Probably has a lot to do with the 7YR stretch from 2008-2015 where they missed on 6 straight 1st round picks (Leblanc, Tinordi, Beaulieu, Galchenyuk, McCarron, Scherbak, Juulsen) and only produced one above average NHLer (Gallagher) during that time.
Their drafts the past couple years look good, but the Habs were unquestionably one of the worst drafting teams the previous decade (2008-2018).
See, problm here is, Habs during those years drafted out of the top15 EVERY draft except the Galchenyuk one... Vs Ottawa who's drafted ONCE outside of the top15. The fact is you'll most probably lose when drafting outside of the top15 for so long at some point.
In the past 15 years, Habs have drafted a big total of THREE times in the top10, 4X in the top15. They drafted Galchenyuk (horrible draft), Sergachev (top 3 dman, they traded him tho) and KK (top 6 C at age 20, still one of the 10 youngest playe rin the NHL RIGHT NOW). Sens have drafted 5 times int he top 10 during those same years, at that's not counting your 2 picks in the 2020 draft. Chances you miss inside the top10 are a LOT slimmer than in the 15-25 range (where Habs drafted most of the time)
And let's be honnest, Galchenyuk is stil a top10 ffeensive producer out of that putrid draft year, and Juulse was trening VERY well before getting those nasty injuries, that's not a Habs problem