Of course building towers-in-a-park as a form of urban renewal (demolishing existing urban neighbourhoods, especially black neighbourhoods) is very bad. But I think that is a problem of urban renewal, not of towers-in-a-park.
For example, the vast majority of towers-in-a-park in Toronto area were not urban renewal projects. They were built on greenfields. Despite their problems, I would say the towers-in-a-park in these post-war subdivisions make them feel a lot more urban. The transit ridership and service levels in these subdivisions is comparable to inner cities, and I think it do with the higher density as the result of so many towers-in-a-park. Mississauga has a corridor where buses comes every 3 minutes all day, that does touch Toronto, and where
LRT is being planned. I think the LRT is the result of all the towers-in-a-park along the corridor. The other suburban LRTs in the Toronto area are the same.
I think probably you can acheive the same density as tower-in-a-park with mid-rises. Towers-in-a-park are out of fashion now. But that's not to say they are inherently bad, especially for suburbs like Mississauga, North York, Etobicoke, Scarborough.
I think maybe the main bad thing about any towers compared to low-rises is in terms of energy consumption, for the elevators. When I went to Montreal, I was fascinated by the elevator-less, walk-up, 3-4 storey apartments buildings there. Apparently, they are called "plexes". It made me realize we don't need high-rises. Montreal is denser than Toronto. Montreal has better transit ridership than Toronto. Montreal is much more beautiful than Toronto. Toronto is simply an inferior and less sustainable city almost every way. Maybe if Toronto didn't build focus on building high-rises so much, things would be different.