Post-punk and the question of whether the genre can function without irony is something worth pressing on.
A lot of post-punk operates through a kind of critical irony — a distance from the forms it uses, a self-awareness about the conventions it's deploying or subverting. This is one of the things that distinguishes it from punk, which was more earnest in its anger, and from classic rock, which was earnest in different ways.
The best post-punk has a complicated relationship to sincerity — it can be deeply emotionally committed while maintaining a critical consciousness about that commitment. Ian Curtis is probably the most extreme example: the sincerity is total and the ironic distance is also present, and the tension between them is part of what makes the music so powerful.
The current post-punk revival largely drops the critical consciousness while keeping the sonic conventions. The result often sounds like post-punk aesthetics deployed in service of emotions that the original tradition would have treated with more suspicion.