Then scroll all the way down, make sure YouTube is selected, and then
click on "Multiple Formats"
(view screenshot)
Scroll to the bottom and change "history" to the JSON format and press "OK"
(view screenshot)
Then click on "All YouTube data included" Deselect all and make sure
ONLY history is checked
(view screenshot)
Press "OK", then the blue "Next Step" button. Change the max file size to 4GB.
Wait for an email in your inbox that will let you know when it's ready It'll really only take 5 minutes.
Download the zip file from the link sent to your inbox, and finally
locate the watch-history.json file ./Takeout/YouTube and YouTube Music/history/watch-history.json