The thing with the yellowbelt is that we built it over multiple generations. Now we "know better," which is great. But even with the kind of progressive zoning we seem to maybe be moving towards, it'll take a long time to punch holes in it and really change it.
If you want to be pragmatic, I don't see anything wrong the hyperdensity thing. Looking at North York Centre (since it's the most mature local example), there's criticism out there, I know, that the density goes a block deep and then it's all houses. OK, but what was there before? One and two-storey plazas. Now there are towers and mixed use developments and some office towers and a North York subway station. If you go there at night, it has a real street life and feels much more like Yonge-Eg than, say, Bayview and Finch.
It was created by policy changes and it seems to me, that's an obvious improvement (and especially when compared to something like Scarborough Centre, which has some density but no urbanity).
You can argue that even better would be if they'd gone all the way and bulldozed everything from Bayview to Bathurst and Finch to Sheppard and replaced it all with 5-storey Parisian buildings and Greenwich Village-style walkups but that's pure fantasy. We're starting where we're starting, with a built form that (especially as you move north of the 401) is basically entirely post-WWII. So the question isn't' what an ideal city is, it's how we can fix the one we have now. This is how it starts, not how it ends.
Again, this form/policy - major density at transit stations etc. - has been on the books for 15 years. Weird to re-litigate it because of pictures that came out last week.
EDIT - just to add some context. We're not talking about redoing all of Richmond Hill from scratch and overnight. We're talking about replacing this, which is already like a walled-off city from the neighbourhood, and with some of the most dispiriting, inhospitable urban form imaginable. Just, perspective about what's going on here, folks.