Disagree on your take on Chicago/Toronto but agree with you that we may have to turn the corner soon.
What else could Toronto have done? They bottomed out and got the number 4 pick (Marner) in '15 and the number 1 pick (Matthews) in '16. They both entered the league in '16-17 with their ELC's expiring after '18-19. How easy do you think it is turn your team from a last place squad to a contender in a 3 year window? They did what they could. Top pair defensemen and top line forwards don't grow on trees, and teams certainly aren't lining up to give them away. They gave Marleau a three year over-35 contract when they knew the last year would be brutal, but they did it to get him on the team and worried about it later. They got Tavares when he became available. This was their year to go for it and they did. They acquired Muzzin for a first and decent prospects. How much earlier could they have gone for it? Who were they acquiring and at what cost? Toronto quite possibly wins the cup this year if they didn't blow a 3-2 series lead to Boston.
The problem the Leafs are now facing, which is completely different from the Blackhawks situation in the summer of 2010, is how bloated the second contract has become for star players. The Blackhawks won their first cup in 2010 when Kane and Toews were on the last year of their ELC. Both then signed identical 5 year deals at $6.3M per. They went on to win the cup again in 2013 and 2015 before then both receiving 8 year deals at $10.5 per. Chicago had 8 years of Kane and Toews, in their prime, to work with before they had to pay them $10M+.
Matthews will be getting $11M+ next year, only his 4th season in the league. Marner most likely will command close to $10M, if not more. The second contracts are out of control now which forces teams' windows to be much, much sooner.
Do I think the Rangers should go after Panarin, Karlsson, etc? No, I don't. But I will fully understand if Gorton and company try to go for it with Henrik still on board for two years and Kakko/Kravtsov/Fox/etc etc all on ELC's.