Yes, you are right. Moving the toy was an option in order to make it easier, if the movement is randomized and controled by the casino software would be ideal for them, since it would decrease the dependence of the winning rate on the player's skill and make the game to get closer to an actual gambling experience.
Also, I would add another idea, they could implement different points for each ring color, for example, 5 green rings, 5 red rings... 2 silver rings but only one golden ring which is worth more crypto in winning, in case the player manages to hook it.
...I don't think that winning many of these games relies on skill anymore.
About the coloured rings, it would be a good addition to the game.
I offered that option just in case casinos need to balance the matches to their favor, because it is well known that some people can get very good at some games and develop very good skills at those games. If the game became too skill based, some players with actual natural o learnt skill could possibly start earning money consistently and cause losses to the casino, which is of course not attractive to them as business.
If the colored rings wouldnt be enough, there are more elements to be added: a timer , adjust the diameter of the rings, adding some obstacles around the hooks, etc.
Whatever the casino considers necessary to turn a skill based game into a luck based one.