Noticed it uses HTML5 canvas to render data by default. To screen readers, am I correct in understanding that this is equally accessible as when people share screenshots of text?

There is an SVG option that looks identical but it doesn't say when you're supposed to use that, or why canvas exists (and is the default) if SVG would work equally well. Then again, setting an example chart to use SVG rendering (I was looking at the basic scatter plot functionality, since I use that most often), I can't seem to tab or otherwise navigate through the data points, so it may just be impossible to get the data read out to you like "first data point, year 2006 students 25 939" (if the axes were labeled "year" and "students", for example; they're not labeled in the example but it could still read out the positions of the points)

I see there are unaddressed requests for improving accessibility:

[Bug] ECharts claims to be accessible, but is not keyboard accessible https://github.com/apache/echarts/issues/18585

[Feature] Support for accessibility of elements inside the chart (series, legend...) https://github.com/apache/echarts/issues/18256

You are asking why Canvas? The answer is simple: Canvas is vastly better performing when given a large amount of datapoints. The difference is not even on the same plane.

Is it even possible to make a chart accessible? I would have thought you would want to hide the chart and expose the raw table to screen readers.

https://apache.github.io/echarts-handbook/en/best-practices/...