I draw the line at downloading data beyond what is required to prove there is an issue and I think you probably should cross that line only when you either have a contract with the company you are researching or if you have a lawyer that you pay that has signed off on what you are about to do. Anything less than that an - imnsho - you are playing the lottery.
Courts, especially in Germany, are typically not pleased if you take possession of the data.
For instance:
https://www.heise.de/en/news/Modern-Solution-Court-of-Appeal...
And quite a few others besides.
As for the absolute facts of the law: the only law I currently have in mind is the GDPR and that is a surprisingly readable piece of legislation.
To be fair, I don’t know for certain whether they will.
However, Lovable was informed weeks in advance. They provided an official statement confirming the findings, which is included in the Handelsblatt article. At no point did they ask us to delay publication or threaten legal action. I can assure you that we would not have published the findings otherwise.
I also want to point out that I contacted Lovable’s head of security directly and shared the results of the analysis: websites, table names, record counts, and an LLM-generated “privacy sensitivity score.” No actual records were shared, as they had already been deleted. He was very cooperative and said his team would review the information and contact the affected customers.
That said, I think that OP didn't cross the line in relation to each company, but IANAL.
It seems far more likely that Lovable and Supabase won’t consider or report this as a breach, nor will they take any action against the reporter.