So I have a trip back to the middle east from Canada in December and I was thinking of choosing the transit phase to be in Paris. Since I find staying in the airport so tiring, I was thinking of staying in a hotel for 24 hours or less in Paris till my flight to the middle east comes. I was wondering if it's possible to do that with a Syrian passport with a Canadian visitor visa that's valid till 2022.
No. You will need to stay within the international zone of the airport. You do have an exemption from the requiring an ATV but those exemptions do not allow an entry in the Schengen area.
Airport Transit Visa
You remain in the airport’s international zone while waiting for the transfer flight to your final destination, and your final destination is located outside the Schengen area.
Airport transit visa
1/ You are travelling from an airport in a country located outside the Schengen Area and staying in the international zone of an airport located in metropolitan France while waiting for your connection to your final destination, which is also located outside the Schengen Area.
You will need a short-stay Schengen visa.
Holders of ATVs are not authorized to enter the Schengen Area. If you have a connection between two airports in the Schengen Area, or if the airport through which you wish to enter the French territory is closed overnight for the duration of the transit, you must hold a valid short-stay Schengen visa.
The same can be confirmed from Timatic as well, every single exemption says that the traveler must remain in the transit zone.
Not all airports in Paris allow an overnight transit, you must double check yours before you go for the flight or you might even be denied boarding without a short-stay visa.
Please also note the comment by @phoog
It probably also should be mentioned that this applies only to those traveling on Annex I passports.