Shanghai and Beijing are not intentionally made to be that dense. The population is large, and you have to cope with that. It is silly to say those cities are not made for people as high density is not a design.
Plus, Shanghai is hardly as dense you think. The city has 23M people on a land of 6300kmsq, exactly 10 times the size of Toronto, with 8 times the population. Is it considered super dense? It is its core area that is congested.
The problem with those cities is not the density, but rather that they are not built for people.
It is possible to build very pleasant walkable and cycling-friendly neighbourhoods at current Shanghai and Beijing densities - but these 2 cities have not done this as far as I can tell.
All newer areas are criss-crossed by what are essentially highways, buildings meet the street horribly, and the public realm is different shades of 'stressful'.
Wasted opportunities all over the place. These cities could be beautiful and functional, but a blatant disregard for human psychology made them as they are. Not unlike Mississauga.
With regards to this project here, what's really important is that we ensure that this area continues to enhance the lives of those who must pass through here regularly. If these towers hurt this block at street level, then they won't be worth it at all.
I would prefer to see these 3 towers pushed down to 40 stories and see the historical facades kept. Fund the museum through whatever means (and call it Princess of Wales gallery), increase the number of retail spaces available (ala Queen and Portland), and build bike lanes along Richmond and Peter (while funding some of the John St revitalisation).
That would be a coherent plan that would guarantee a truly world class strip. The impact on our skyline as seen from the Lake wouldn't be tremendous, but Torontonians don't live and work in the lake, we ought to prioritise our streets.