One of the goals of this law and similar efforts is to make it clear that you need to consider the social, ethical, and legal ramifications of the things you crate. You are not creating neutral things in a vacuum; there is no neutral ground in a burning world[1]. That "small thing on the internet" might be reuniting families that were separated by work or politics, or it might be undermining the support structures of an entire industry or community. Maybe you are creating a social space*, which includes a duty to manage that space to keep so it doesn't become a tool of abuse[2]. Maybe your small site stays small. Obviously you cannot be expected to foresee every potential consequence of your creation, but you at least need to make the effort and catch the low-hanging fruit (e.g. the basic privacy features enforced by the GDPR).
[1] http://opentranscripts.org/transcript/no-neutral-ground-burn...
[2] http://www.gdcvault.com/play/1024060/Still-Logged-In-What-AR