It takes 30 seconds to find out whether your identifier violates a trademark. Your content is trivially not a copyright violation if you created it yourself. Hobby projects are not debating the finer points of fair use and whether the conflicting name is for a sufficiently different kind of business to avoid confusion. But every HTTP server handles personal data, and a web-based tool with a database backend especially so, so all the subtlety of GDPR is in play.
It takes 30 seconds to find out whether your identifier violates a trademark. Your content is trivially not a copyright violation if you created it yourself. Hobby projects are not debating the finer points of fair use and whether the conflicting name is for a sufficiently different kind of business to avoid confusion. But every HTTP server handles personal data, and a web-based tool with a database backend especially so, so all the subtlety of GDPR is in play.