I do not know a lot about Canadian politics, but just looking at the history of Canadian PMs over the past few decades, it does appear that 9 years in office appears to be pretty normal, so Trudeau's resignation as PM and party leader is not a surprise:
Justin Trudeau has said he will step down as Canada’s prime minister after his party finds a new leader, a decision that in effect brings an end to nearly a decade in power.
“Canadians deserve a clear choice in the next election,” Trudeau said, adding that party infighting had made it impossible for him to face off against his political rivals. Trudeau said would stay on as prime minister until a new leader of the ruling Liberal party was chosen through a “robust, nationwide” process.
His resignation throws open the doors to a fierce political battle to be the country’s next leader, with polls showing the Liberals losing badly to the official opposition Conservatives in an election that must be held by late October, regardless of who the leader is.
Trudeau, who used his address to recount his government’s accomplishments over three terms, said parliament would be suspended until 24 March.
He has become increasingly unpopular in the last 2-3 years, and with the resignation of Nazi apologist Chrystia Freeland from the government, allegedly because he was unwilling to hurt the poors as much as she wanted to.
I expect a shift to the right (not that Trudeau was anything but right-of-center) and a drubbing in the elections, with the Conservative Party of Canada (CPC) winning by a lot.
I would hope that the New Democratic Party (NDP) gets enough votes to be the official opposition party, but I am not holding my breath.
I expect that whatever government that comes out of this, it will spend most of its time sucking up to President Musk.