The first thing I would like to say is this rule does not eliminate turn player priority like most people assume. This rule really only changes how turn player priority works.

You see there are three spell speeds in Yugioh as you all may know. Before the rules change spell speed 1 monster effects were allowed to be activated with Turn Player Priority upon summoning them. This ment you could not activate a trap or anything like that to stop a spell speed 1 monster effect.

Spell speed one monster effects are called Ignition effects. These effects have some kind of activation cost to use them. Cards like Snipe Hunter, Cannon Soldier, Rescue Rabbit, and Dark Armed Dragon are all examples of ignition effects because they make you make the desision of when to use the effects.

The common misconception here is that all monster effects activate this way. This is not true. There are multiple different monster effects.

The most important of these effects is Quick Effects. The reason Quick effects are important in this conversation is because Quick Effect monsters are uneffected by this rule. Quick Effects are spell speed 2 effects that you can retain your turn player priority to use. Quick effects are any effects that can be activated on either players turn. Cards like Strike Ninja, Wind Up Rabbit, and DD Crow all fall into this catagory. Since there effects are spell speed 2 they can be used with your Turn Player Priority.

The next effects to talk about are called Triggered effects. Triggered effects are also not effected by this ruling. Triggered effects happen in response to something else happening. In Yugioh most of these are summoning effect. Cards like the monarchs, Breaker the Magical Warrior, and Black Rose Dragons first effect are common examples of Triggered effects. Because there effects activate upon summoning they will still get there effects against cards like Bottomless Trap Hole for example.

The last type of monster effects and the ones that are effected the least by this ruling are Continuous monster effects. These are effects that take place upon summoning and are immediately activated if the monster resolves.

So the actual rules change works like this. Konami decided that you can no longer retain turn play priority to activate your spell speed 1 monster effects anymore. So you still have turn play priority to activate spell speed 2 or higher effects like Quick Effects, Traps, and Quick Play Magic cards, you can just no longer uses spell speed 1 ignition effects with your Turn Player Priority. I hope this helps with the confusion.