It's still relevant as deployed Adlo in bleeding edge progression will allow low ilvl parties to survive that raid buster mechanic where as Aspected Helios won't do the trick. This is because Adlo synergizes excessively well with a WAR who's under Defiance and Convalescence. To put that into perspective:
Adlo base shield = 300p * Defiance (1.2) * Conv (1.2) = 432p
Aspected Helios = 150p * Noct Sect (1.1) * Shield Bonus (1.5) = 247p
Mantra ignored since it benefits both Adlo and Helios equally in this scenario. Additionally, Fey Illumination and Synastry are both ignored as well since they give the same bonus and chances are if you're an AST partnered with a SCH you aren't in Noct.
Adlo is still 74% stronger in this scenario.
You can make the argument that Disable can mitigate another 10% on top of Soil / CU that Supervirus can't if it's Darkness damage but I'll save judgement on that until one sees the type of raid that's released in 3.4.
What Noct gives now is consistent mitigation versus SCHs more raid buster stopping CDs (this is only from a mitigation standpoint though, don't really want to delve into what the rest of the SCH kit gives them).
The changes won't be a substitute to SCH for bleeding edge progression butit'll certainly be much more viable to run WHM/AST if so desired for the non-bleeding edge progression groups. [EDIT] I'm actually going to renag on this comment. Depending on how the fights are designed the consistency of Aspected Helios may overwrite the necessity of Deployed Adlo depending on the fight designs and just when/where the raid busters occur / how often then occur. But if there's a massive raid buster that can only be survived with a fully buffed Adlo going out, well, you know what that'll mean for Noct vs SCH in that scenario.