In 2006, three weeks after the airing of the Water Play episode, tragedy suddenly and unexpectedly struck the Doraemon 2005 anime. For one reason or another, parents groups complained about the episode featuring too much nudity, which negatively affected production of a future episode. The episode, which was already completed, was scheduled to air three weeks from then, but due to the complaints, the staff had to censor it in a very obtrusive way, using large amounts of steam that blocked everything.
This had a very negative effect on the nature of Shizuka nudity on the show. From then on out, all scenes with Shizuka in the bath were comparatively censored to not just their original counterparts, but to scenes that had aired just previously! She'd only be seen shoulders up, her whole body hidden in silhouette, or she'd be wearing a towel or something heavily covering. Of course, none of this level of censorship made it to the boys, predictably and cowardly. They still got to show a lot, save the privates they used to.
The picture on the bottom I've provided is not a typical censorship reduction picture. Whereas it was never the intent for other examples to be anything other than censored, this one represents an attempt to bring the picture closer to the idea of the original intent. To that end, Krizeii did well; he didn't show things on Shizuka that weren't allowed in the original anime.
But that the girl has her scenes butchered while the boys go off free, in an anime that has previously never done this... that's a tragedy.