When I retired...I had people ask me...aren't you going to be bored??? When I go and visit them if I am in town where I worked...they ask, are you bored yet?? I say (and will always say) No Way!! I always find something to do.
I had a couple people ask...I would be bored. I tell them, get a hobby, volunteer, etc.
Maybe because those that say they would be bored...live in apts and don't have the option of doing garden or yard work and/or don't have hobbies. I feel then it is a great time to start a hobby. But I also say "You make it..what you want to". If you think it is going to be boring..then it probably will be.