pokemon – How does the Veevee ‘Volve ability work?

The Veevee ‘Volve ability says:

This Pokémon can evolve into any Pokémon that evolves from Eevee if you play it from your hand onto this Pokémon. (This Pokémon can’t evolve during your first turn or the turn you play it.)

This just sounds like how evolution works in the card game?

Looking up how it works on Go Hub:

We begin with the poster Pokémon of this set: Eevee EX. Thematically, it headlines the expansion but when it comes to battle, it is probably the weakest EX card until now. Its only flavor is its ridiculously named ability, Veevee ‘volve, by virtue of which Eevee EX can be evolved into any Eeveelution, EX card or not.

It sounds like the card being an ex card changes how evolution works, but I tried to look into it and all I could find was this:

A Pokemon ex card can be played in the same way as Pokemon cards. Basic Pokemon ex cards can be played right away without evolving them, while Stage 1 and Stage 2 Pokemon ex cards require sending their previous forms in the field before they can be played.

— pokecardhq

So what is the point of that ability?