The difference is what is in the full frame.
Interlace has half of one frame per second, and half of the next frame per second. So as a puck or ball is moving, half of the image the ball moving is being produced by one frame...and then half of the next frame is being produced to help track motion. Interlace dynamically changes the frame you see by...interlacing..present and "next" frames together. This gives you motion at 60 fields per second.
As oppose to progressive... where it just produces one full frame at a moment of time. One field per frame, nothing being interlaced together. So if it is going slow enough (below 60fps), you can notice stutter and trails.
There is a reason streaming services are striving for 60fps on their channels...and it is because they cannot interlace frames. You can google any streaming service and see that they are all striving for 60fps. They wouldn't be striving for 60fps and clogging up the streaming service with more data per second for giggles. There is a reason for it.