Land economics studies on highways actually suggest induced demand brings things back to a congested state within a couple years, as so many people (me included) were avoiding the Gardiner during these lane closures.  (I honestly only will use it if I am taking someone to the airport, otherwise it is transit always that gets me places faster from the east side.) Adding lanes is like loosening your belt to cure obesity.
Personally, I would far prefer we funneled more moolah in to transit to achieve European levels of service, full on transit priority for LRTs/Trams, and removed highways that travel through our downtown, but that's me and I realize I may just have to move elsewhere to experience that zen I seek. I am fully for disincentivizing people from driving downtown altogether.
		
		
	 
People say this but it just doesn't bear true - especially not in areas that don't have high population growth where demand predictably increases with population.
I mean you can see it with the Gardiner itself. 2 years of closures and traffic remained
 substantially worse than immediately pre-closure. That traffic didn't evaporate entirely. Much of it did, but not entirely. The same thing goes in inverse - new infrastructure induces more trips (this is true with transit too!) but does not automatically mean traffic will return to the same level of congestion. The Gardiner reopening will now induce more car trips than were running on it last week for sure - but overall traffic and travel times will remain below previous ones too.
Frankly the east end of the city is the most difficult part of the City to drive in, especially post-demolition of the Lakeshore ramps. it's not a surprise transit is faster, but that's not always true for most people. A lot of people and goods simply have to drive as well as they are bringing things which aren't practical on transit - dump trucks, construction equipment, etc. will still need a way to get downtown.
Urban Expressways even in Europe are more common than many portray here as well, though they do tend to go a bit further from the immediate downtown. Paris has the Blvd Périphérique which would run around Toronto roughly from the DVP to High Park and across around Eglinton in terms of size, Berlin has the A100 (recently extended closer to downtown!),  Amsterdam the A10 loop, Barcelona the B10, etc.
The cities in Europe without big urban expressways (i.e. London) have large, congested arterials that are equally unfun places to spend time around.
In places like downtowns we shouldn't be building massive expressway networks so everyone can drive downtown. We know what that results in south of the border (even then, some cities like Chicago still have ~80% of people driving into the City and it's still a relatively successful urban place) - but pretending we can live in a car-free utopia in 2025 is also a folly. We need a reasonable amount of highway capacity in inner cities to shift freight traffic off of local roads and allow local streets to be more people-focused. Induced demand is also something which is thrown around like it's some indisputable fact everywhere online while in reality it's a wild misinterpretation of data. Induced demand is real - it's just not infinite and the infinite part is what people get wrong.
new car infrastructure DOES:
1. induce new car trips
2. Encourage people to drive more often and set lifestyle habits around driving more often (i.e. living further outside of the city instead of an apartment downtown)
3. create economic growth
4. improve transportation choices and mobility
5. Even with increased demand, result in more people getting to their destination in a method of transport they prefer (otherwise they wouldn't be making the trip)
new car infrastructure DOES NOT:
1. automatically induce so many car trips to completely offset travel time gains. Perhaps travel times remain the same, but the infrastructure would then be supporting a much larger population (i.e. Houston with the most often quoted Katy Freeway) and travel times would have declined without the infrastructure.
2. create the kinds of cities we generally want to see.
3. Induce so many trips that the economic value of the infrastructure remains the same (even if travel times remain the same, more people are making the trip!).