Closed-backs are typically treated as the lesser sibling of the open-back, with "poorer" technicalities and a less open stage. Nevertheless, it has its inherent advantages; for anyone searching for a robust and thoroughly engaging basshead presentation, the closed cans are usually the better choice in that regard.
With that being said, the new T5 has a polarizing sound, within the referential frame of the classic audiophile, IMO. However, for fans of a liquid, textured signature, the revised T5 does actually sound pretty decent. The bass on the T5 (3rd Gen) is potent, with a vigorous boost that helps create impactful lows.
In any case, what truly matters is whether you enjoy your headphone, so in that regard, the T5 appears to have fulfilled its objective.