Some of this is a LITTLE bit revisionist history.
A lot of the brands that closed recently have been very mid-market: Pottery Barn, Williams-Sonoma, Gap, HBC, J. Crew, even Banana and Brooks Brother's aren't exactly luxury. I mean - Winner's replaced Chapters; it's not like Winner's replaced Barney's.
For most of the past 40+ years, the primary mono luxury brands on Bloor were Channel, Hermes, and LV. Tiffany and Co was the first new mono brand to open in then 90s and since then it's been a drip of openings. After the failure of Bretton's, Creed's in the late 80's and early 90's, there was ALWAYS a lot of mid-market on Bloor and in Yorkville (think Nike, Benetton, Browns); if anything, Toronto didn't have much of a luxury retail strip especially when compared to similar, or even smaller, American cities.
Over the past 20 years we've seen way more global luxury brands open in Bloor / Yorkville, and we've also seen a similar number opt to open in Yorkdale, which as mentioned above has stolen a lot of Bloor+ Yorkville's thunder. We've also seen the rise of Yorkville Ave, which has 7 large luxury mono-brands, which was NOT a luxury hot-spot even 5 years ago.
To be clear, the pandemic was bad for Bloor and unlike Yorkdale, Bloor doesn't have a single landlord to market retail spaces too, but the demise of Bloor is a bit of a stretch, in my opinion.