Yes, it is. Here is my approach.
Watch what I created
The definition in the video finds inflection points as following order.
It creates an object which has two lines as above picture, and transforms it to several points on selected spline.
And checks each of the transformed objects by using DoesIntersect node as following rule.
A simple Python Script was used to make this work easy. The code returns index when both booleans are different from each other.
Another python node was necessary, because Dynamo finds multiple continuous points when the curvature around inflection point is small. The second script finds each of average points from continuous series of points as follow.
Then it collects inflection points by using above result as index numbers.
Oh, and you can adjust accuracy as follow. The bigger number the more accurate points you can get.
You can download my dyn as usual.