It was undoubtedly ambitious in the pre-covid market. IIRC the 10,000,000 of office space originally planned here represented about ~10 years of office space absorption across the entire GTA market, and was proposed by a single landlord in a single location which is not exactly the most desirable office location in the city, albeit a good one. Perhaps not impossible, but absolutely highly ambitious.
I never stated that I thought office space here should be eliminated. Ultimately however CF is still officially planning 10,000,000 of office space here in a market which will be lucky to see an absorption rate at half that of the pre-COVID market and which is experiencing a "flight to quality" - i.e. new space around Union Station.
I do think we will see office starts again within a few years, but less in less prime areas and all starts at a slower pace than before COVID. I imagine that yes, CF could manage to fill a few buildings here over the long term. But not anywhere close to 10,000,000sf.