Be aware,
Youtube can backfire on you. My granddaughter thought she'd show her brother how "safe" POTC was. Nope, he saw the "fast" drop, and it was ruled off limits.
Oh, and when he was 4, we did get him on the swings, riding tandem with his favorite "helper" (I have a couple teen/now 20 yos who come and help with the kids on trips) when she gave him a "bravery card" (simply an old day ticket) which he put in his pocket and it made him brave. And it was a ride he would ride over and over (but only with his bravery card.)
This is a kid who got to spend his 4th birthday at a preview for Galaxy's Edge, and we did get him to see the "show" Smuggler's Run, more than once! But POTC was too "fast".