Not that I know of that is simple.
But if you only have a Main timeline animation, you could place a keyframe action at the start of the timeline to jump to the end time of the timeline.
Then export png sequence.
The export duration will show 0 duration, don't worry about that
You will then only get the last frame instead of hundreds.
Last export frame
If you have other timelines including ones in symbols then the above will not work since you are by passing them and to try and do the trick on all of them would be a bit of a waste of time where you could then just grab a playing animation from the preview and built in screen capture actions on the Mac.