Thanks, Marina! This continues to be an issue in Moodle 3.4.
The CSS workaround you provided is very helpful in reducing the size of the charts.
However, the text in the charts is displayed as an image and thus loses the ability to wrap or be resized or recolored for easier reading. If the question is long, only the last 49 characters of the question display.
I can use the "Show chart data" option to view the full question, but then the person reading the report has to look one place for the visual representation of the results and a different place for the full question.
Is there any way to return to the old display where the question and bar chart of responses were side-by-side and could be easily styled with custom CSS? Comparison examples below.