If my understanding is correct (with the caveat that I am nowhere close to an expert), that's frankly bonkers and I have no idea how Twitter can operate at all in Japan.
Being absurdly protective of the person who did the work is at least erring on the side of protection.
It's not impossible to imagine a world where the internet could have social media platforms with some attempt at media attribution functionality...
...instead we have the wild west where the vast majority of content is shared without acknowledgement, let alone attribution or permission. Even EXIF attribution data is stripped whether you like it or not. You have incredibly successful artists trying to protect their work with watermarks and JS-disabled right-clicks. Seems silly.
Uploader stole a pic and posted it, which normally constitute a consent to ToS, or something like that. Others unknowingly retweeted the stolen pic and the photographer wants their identity disclosed to proceed with lawsuits.
Twitter argued that retweets don’t count as distributing and requiring a click to show full photo isn’t cropping, but the court determined it does/it is.
Counterintuitive way to draw a line but I’m not sure if it’s terrible that court find cropping the photo with CSS require user consent. Maybe not as bonkers as Coinhive case.
Note that usually people are reasonable about it, and that it's also extremely common to have contracts state the right will not be exercised. This case is unusual because the use of the photo is completely non-consensual.
The photographer may be in breach of Twitter's ToS for enforcing their moral rights, but that would not _stop_ them from enforcing their rights. In this case, the initial post to twitter was not from the photographer, but someone else. So Twitter likely has nothing to hold against the photographer.
Nothing in the article suggests any agreement between the photographer and Twitter.