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>patternfagging with one point of data
They didn't, they had no set roadmap of prior releases that would hint towards them following the release or remake trope, which was its own separate thing (as evidenced by them starting L: A based in old Sinnoh, but accepting a remake may be needed because of demand).
Legends seems to be a look into the early days of human/pokémon relationships as we see in the modern era. When people initially developed a pokéball to catch and carry the magical elemental creatures they lived alongside to drive the revolution of their society into the modern world we see today (L: Z-A's blurb stating Lumiose is undergoing a redevelopment project with the aim of building a city where people and pokémon can live alongside one another). And as such, has no remit to follow release order or to act as a not!remake, when Game Freak already stated internally they wanted Legends to be different from the usual remake, a new direction for the series.