Taking a character's old build path and applying it as a reason as to why they shouldn't have been VGU'd to fit a theme better is not how character design works at all.
Irelia has always been described as a nimble fighter using telekinetic blades in almost all aspects of her lore, with nothing seeming to note that she's an unkillable juggernaut who marches up to you and just takes blow and after blow and doesn't seem phased by it. In this sense, Irelia's lore and original fantasy (the nimble fighter using telekinetic blade) was creating a massive disconnect between the class and build style that she had become as time and nerfs wore her out (bruiser). Because of this disconnect, they reworked her into something that fit her fantasy a lot better, and gave her the feeling of a nimble telekinetic blade user.
She will most likely not be building tanky anymore, because she'll most likely be geared towards being a higher damage duelist who can't afford to build too tanky without it impacting her damage output. I'd wager she'll build Trinity Force and that's about it.
