Is it really a condos or steel dichotomy? We're not losing both companies here.
It seems that if Stelco shuts down (as its workforce has been hacked to a fraction of what it was before, they have newer, if less comprehensive facilities, elsewhere, and they've already done temporary closure) that would allow a wide range of redevelopment and many times the amount of people employed there. Imagine a Master Waterfront Plan that included all of that land too- with retail, residential, commercial - and a remedied waterfront all the way.
And then a commercial buffer, and then Dofasco.
We don't lose our whole heritage. No one's saying "pardon my lunch bucket"

But we do gain a well-situated chunk of land that will only be more and more in demand as the surrounding areas continue to increase density and drive up their prices, and as we (eventually) limit sprawl creates a huge chunk that can be better used than keeping that few people employed - and can potentially employ ten, twenty, a hundred times as many over a variety of uses.
When we have a set of circumstances like this, is it better to keep 700 or so (which is what we have left after the retireees) employed on a large chunk of land, especially when steel no longer has the distinction of creating well-paid entry level jobs, which are quite rare and getting rarer, but jobs that have similar education requirements as other entry-level college-education jobs..................... or to start looking long-term at the future and seeing what the potential for that land could be for many different employers?
Not everyone will agree, but I don't think it's an either/or.. I think it's both/and.