Don't lose sight of the reality that the Sens youth have also been surrounded by UFA & trade upgrades to their top 6/4.
Gallagher, Armia, Savard (13.5M) are not
Giroux, Tarasenko, Chychrun (16M).
I don't think there's much doubt that the Habs group & youth have far less established talent supporting them then the Sens do.
The Habs are still digging out of Bargainbin's terrible cap management & have yet to make any significant intentional UFA/trade additions of established talent... Choosing instead to target adding unproven youth with high potential (Dach, Newhook) & accepting the bumps that come with icing a young roster lacking the veteran talent the Sens were in a position to go out and get.
Upgrading Petry to Matheson, waiving Armia, jettisoning Hoffman for futures... These were all tinkering moves to slowly restructure the roster & cap. That approach means Suzuki/CC/Slaf aren't surrounded by vet talent that can share the burden of nightly performance.
Over next 2 years, I think we'll see some legit reinforcements brought in, until then we will have to take our lumps & avoid making apples to oranges comparisons.