It's not the dollars it's the term. They'll be better next year and the year after, maybe even be on the fringes of the playoff race now but deals like this are going to be the difference between them keeping their team together and having to offload significant pieces. Even if JP, Draisaitl and McDavid only get 20 mil or so, trouble ahead cap wise, and they are still lacking two real puck moving defencemen to be an actual contending team imo. If they sign Demers to a long term deal now, they are totally screwed.
But for their fans, after all the misery, I'm sure just having a competitive team again will be nice for a change, and I think they will be.
If they were smart would have chased skilled players instead of paying the goon premium just as fighting is disappearing from the league though. It seems like their mgmt became obsessed with fighting after McDavid went into the boards as if it was somebody gooning him or something.