Since it seems Dubas is apparently locked in stone as long as Shanahan is president and his boss, and the results don't seem to matter, then the next big pressure point in this question will come in 2 years time when Matthews contract is up.
Dubas
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gave Leafs franchise player Matthews only a 5 year deal, because he spent so much on UFA Tavares, that he couldn't no longer afford for cap reason, to instead lock Auston for 8 years which should have been priority #1 and an organizational mandate, similar to Connor McDavid.. So now Leafs losing in round #1 year after year, after year will impact Matthews decision to stay or go. Leafs losing and players leaving a sinking ship will be related. IMO
Matthews legacy already includes 6 straight round #1 losses, and so without any further success next year, then he will have a higher chance of leaving than staying to chase Cup success elsewhere, for himself and his reputation alone.
Should Matthews leave not only will it send the Leafs back into a rebuild cycle, but an angry mob in Toronto with pitchforks will come looking for Dubas head on a spike for not getting the 8 year term, and looking to tar and feather and to be
hanged, drawn and quartered like they use to do in the olden days for treason, which is equivalent to losing your franchise player due to your own actions at the detterment of the organization. Dubas will need to be relocated into a witness protection program for his own safety as the fan base and the media will be looking for blood.
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My point being eventually the results will matter, and it might be Matthews that forces that change to happen, and repect in a handshake line no longer good enough to keep the status quo among all the losing.
The clock is ticking....