As part of their deal with the Liberals, the NDP had some real power to implement legislation. If an election happened tomorrow the NDP would lose that power.
Unhitching from Trudeau at this moment is a good move for the NDP, they want to distance themselves from Trudeau's unpopularity before the next election. That Trudeau is now leaving benefits them even more, they could conceivably continue to support the government now that it's missing its most unpopular member, or they could pull the plug right away if they think they can steal away some Liberal votes during a snap election
It really isn't - the alternative is it's the most unbelievable happy coincidence.
You have to wonder how blatant the personal moneygrabbing by Lib and NDP leaders has to be before their respective support bases actually accept what is going on in their faces. Those leaders see the parties purely as a way to secure power to use to gain personal wealth at the expense of the populous.
It's not though.The NDP were faced with two choices:
1) Support the Liberals and get some of their policies pushed through 2) Support the Conservatives wish to call an early election in which the Conservative are sure to win a majority leaving the NDP powerless
The reason why the NDP choose this moment to pull their support is that it's an election year, so there's little chance any more NDP policy would be passed. One person's pension (a relatively wealthy person at that) is just a fun partisan talking point for Conservatives.
During his delusional ramblings (and that is no exaggeration) Trudeau said that the GG was persuaded to prorogue to the 25th March because of the no confidence vote held back in December which he survived because the NDP supported him. The NDP no longer will support the Trudeau gov (announced in writing about 10 days after the last vote), coincidentally just as their leader qualifies for a nice parliamentary pension scheme.
The whole thing is a horrible exercise in the worst stereotypes of champagne socialism.