It seems you haven't watched much. Just 3 TV series and just 9 movies. I didn't know there even are people who watched this little in their lives.
By the way I once knew an magically amazing website to mark what you watched and discover what to watch. It was Jinni.com. It was an absolutely mind-blowing experience to browse. It would present you a collage of posters, you would mark what did you watch and how did it feel and it would suggest you movies/shows similar in various aspects (atmosphere, mood, specific themes in the plot, genre and more subtle ways). It also had a social function so people could share and see what others watched I can hardly describe how much I loved it, it was a perfect recommendation engine, no where to be challenged by any else existing to the day. For me it's a tragedy it closed and only makes money by selling their data to adtech corporations apparently.
I've watched 1000+ movies & shows. Just started to track them last month on my personal site.
I can always use IMDB or LetterBoxd but I want to de-risk loosing all my work if a 3rd party company tomorrow decides to shut down or gets hacked. With my own data, I always will have a backup and lifetime uptime guarantee.
Movie data isn't that valuable information to protect for an individual. Instead you can try making a contacts syncing software, or email storage, or even WhatsApp media backup system.
By the way I once knew an magically amazing website to mark what you watched and discover what to watch. It was Jinni.com. It was an absolutely mind-blowing experience to browse. It would present you a collage of posters, you would mark what did you watch and how did it feel and it would suggest you movies/shows similar in various aspects (atmosphere, mood, specific themes in the plot, genre and more subtle ways). It also had a social function so people could share and see what others watched I can hardly describe how much I loved it, it was a perfect recommendation engine, no where to be challenged by any else existing to the day. For me it's a tragedy it closed and only makes money by selling their data to adtech corporations apparently.