Not without funding they can't. Cities got all the responsibilities for transit and housing, but none of the funding they used to go with it. The feds and provinces need to pay up, and fund cities properly, or give them autonomy to find their own funding sources.
A big part of why our cities are broke is because they have to maintain roads, sewers and other infrastructure in areas that give back very little tax revenue in relation to the amount of infrastructure they require. Those cost centers are are low-density suburbs with single-family homes.
Once mid-density housing is allowed to flourish, especially mixed-use buildings, funding and other problems disappear: tax revenue increases in relation to liabilities, frequent public transit is economically feasible, traffic is reduced as more people are able to go about their daily lives without a car, and the reduced car traffic means streets become quieter and safer.
This is part of the problem, Toronto specifically has to pay for two highways that are almost entirely used by people who don't pay for them. Building that middle density housing would fix a lot, but we'd actually still be in a difficult financial position, because municipalities here are so limited in how they can generate income. The province can override any decision a municipality makes whenever they want, and that neede to change.
By providing all that shit for free, we've basically been subsidising lifestyles that are otherwise wasteful. And then we added low-density zoning on top of it, so here we are.
I'm not on the private roadways "train" (lol), but I think they should be self-funded by a hypothecated tax, or user fee depending on how you want to look at it. If we did that, public transit would probably grow itself.