the pokémon data structure has been forwards-compatible since November 21, 2002, over twenty years
this is not as old as javascript, css, or xml, but it is roughly as old as the first JSON and YAML libraries
the previous pokémon data structure, which IS as old as (standardized) javascript, was later made forwards-compatible (with the virtual console releases of red and blue on the 3DS), but since there is no way to get a pokémon from a game boy game into the current ecosystem i’m saying that the original pokémon data structure as present in the original physical games still doesn't qualify
but you COULD argue it does
@Lady I think the notable thing is that, while they were still in regular active use, there was no way to carry them forward.
So even if they made a physical adaptor now, that you could plug the actual game cartridge into and transfer them, I would count that as... archival-work? almost? rather than forward-compatibility.
@gaditb yes, although i think there is an open question as to whether they were incompatible in design or incompatible due to there being no technology for communicating between a game boy and a GBA
in the latter case the data structure might be considered forwards-compatible but stranded
however, i'm not sure i believe that; i think it was never intended to be bridged even though they later did find a way
@gaditb (importantly one of the ways they bridged it relies on hidden abilities, which would not be introduced until gen v
now, they didn't HAVE to use hidden abilities; when they bridged pokémon let's go (which used basically the same data structure) they just randomized the abilities instead; but the currently implemented transform could not have been applied in gen iii)
