I worked at Famous Players before it was bought out by Cineplex during the late 90s to early 2000s. I'm still scarred from cleaning after Harry Potter, Monsters Inc and the Blair Witch Project showings. Back then, theatres were packed and sold out every weekend. It is really sad seeing the state of these cinemas in the current situation.
The 2017 cliff dive is from streaming service becoming readily available en masse. Amazon Prime video launched internationally the year before and that really was the nail in the coffin. I really hope Cineplex does not go bankrupt but the way things are going, it's not looking good. And I'm not sure if they can last another 6 months for the new Bond movie.