There's been a number of times this season that felt like they could be a turning point for the team to get back to last year's heights, only to have the inconsistency kill the momentum a game later. But 4 straight in my mind where we looked clearly like a team that was either even or better than the opponent and having everyone (outside of Seigs/Hamilton) healthy is enough to give you hope that this time might be for real. No reason at all to believe it is too late.
Just playing devil's advocate. If one of the tenants of the apparent systems change is to put more onus on the centers to play a more traditional, defensively responsible center role (which is certainly what it appears to me and what the announcers have alluded to), then Ruff may not have felt like the team could effectively handle that with McLeod as their 2nd or even 1st line center in some games, Haula in and out of the lineup/unable to play C for a chunk of the season for some reason, Mercer having to play C, and Tierney/Willman getting regular time. It's entirely possible Ruff recognized they needed to make a change but just didn't think the personnel he had available could do it. Upgrading from Hichier-McLeod-Lazar/Mercer-Tierney with Bowers and Dowling thrown in there sometimes to Hughes/Haula-Hischier-Lazar-Nosek is a major improvement to every line, given who it means is on each wing as well.
I don't necessarily agree with that conclusion if that is the case, but this is why it's difficult to judge coaching decisions when the coach is working within roster limitations. I feel like both the "it's all the goalies fault" and the "it's all Ruff's fault" crowds have been ignoring the elephant in the room that our roster, particularly at center, has been filled with AHL talent all season due to injuries and that is finally not the case.