The KCGP World leak was either fake news or they gave up on it. Its main characters are having most of their cards being released in boxes or rank tickets.
Yep, characters don't absolutely need ace card anymore ever since we got Tristan. All we need is that there are cards related to their deck theme that can be used as level up reward and drop.
That mark of {X} skill for 5d is just advertisement that says.
See how powerful these cards are when you use them, and you can have one for a very cheap price of 9000 gems.
Not enough gems? Then how about the very cheap price of $30 for 30 packs?
I think it was real and it makes a lot of sense. Arc-V world in 2021 is way too soon since konami is still promoting Synchros a little bit and it's just just started with Xyz monsters and those can be milked for a lot of time. Zigfried might come with some anime cards, ride of the valkyries and so on, same for leon, rebecca and yugi's grandpa.