Disclaimer: I know there are multiple threads around this on StackExchange and all over the internet but I'm re-posting because half the information in there is outdated and none of them offer a perfect solution (yet).
Problem Statement - There are multiple duplicate photos on my Google Photos account, some of which are duplicated 3-5 times each over the course of multiple backups in the last 10 years. Given the volume of photos (1000s), it is impossible to segregate and delete thee duplicates individually. Google has retired Picasa (which had an experimental duplicate finder). Moreover, they've also stopped syncing between Drive <> Photos which used to be a hacky way for folks to download all photos, use an offline deduplication software and re-upload. Google has acknowledged the problem and has not provided an update for years now and it doesn't seem like it's on their near-future roadmap either.
Has anyone here been able to successfully find a solution to this that works well? Maybe download all photos (though it's painful to select all inside Google Photos as well) and de-dupe script that could be run to identify duplicates and re-upload the best originals? This is a legit problem I've seen 100s of people talk about over the internet and indeed a great monetisation source for someone who has the skill-set to build a working solution.