There are a couple a key ways to tell a Shadowless version versus an un-limited version Charizard
Some collectors want all the rainbow rare cards, others seek out only illustration rares, and others love collecting every copy of their favorite Pokemon
Its ability, Broken Space Bellow, allows you to attach a Psychic energy from your energy zone to itself even though it ends your turn, this setup lets you build threats passively while your other attackers engage
My guess is that it'll slowly fall back down to a lower value - but that process could take months or even years
Two-color decks that dont have access to much ramp and can afford a few colorless mana sources can make good use of a Myriad Landscape, whereas green decks and 5-color commanders have much less need for something like this
I am reminded of this every time I open Pokmon TCG Pocket to battle a stranger