Flew out & back from Canada on Transat just before the lockdown kicked in. A lot of folks are critical of AT at the best of times, but as a fairly regular user, & high mileage business flier, I can't really say I've had anywhere as many issues with AT as I've had with other carriers.
Given the lack of understanding about transmission and governmental guidance at the time, I found the cabin & flight crew were well organised and very savvy about how they went about things. Flight crew gave longer briefing than normal, explained about ventilation system on plane. Cabin crew spent time well shuffling the cabin before pushback - kept families together, tried to spread others about the cabin as much as possible putting as much space between folks as possible, asking people to wear masks if they had them or scarves, snoods, etc. if not. Flight crew asked people to stay in seats as much as possible, use call buttons well ahead of time/need if you wanted to get up & about & wait for Cabin Crew to come to seat & shepherd them to minimise hanging about at galley / toilet etc. Worked very well on a fairly busy flight.
I have NEVER seen Pearson airport soooo eeemmmmpppppppttttyyyyyyyy......... you could have held three Stanley Cup games and a half dozen football games in the check-in areas without disrupting the few passengers that were there. This side was even worse, I was anticipating that some sort of Day of the Triffids / Zombie Apocalypse had taken place by the time I wandered through Arrivals without seeing another single, solitary soul.