The IPO is fucked regardless of what reddit does next, they are in a lose lose situation. Anyone who thought they would turn around and change their mind is delusional and doesn’t understand how maniacal CEOs work
In fairness, the IPO was probably knackered already. One of Reddit's main investors, Fidelity Inc. dropped their valuation of Reddit shares by almost half some months ago, and I can't imagine that would do particularly good things to any IPO efforts that Reddit might have been trying to pull. Were I an investor, I'd probably steer away from Reddit if their valuation suddenly plummeted by that much.
Never mind the whole API changes lately, which both puts the users into an uproar, and makes a mess of things that could cause advertisers to pull out, dropping their revenue even further, and the AMA/Interviews with the CEO don't only show the CEO to be a liar, but have him admit that Reddit is unable to make its own first-party app profitable, unlike third-party apps that let users access the site, which smells like mismanagement. I'd have a lot of questions, and none of them are good.
I wouldn't be at all surprised if the recent changes were an effort to try and salvage their stock price, by pushing AI, and bumping up their revenue by making AI companies pay to use the API to integrate their models with Reddit, and/or as a way to pump and dump Reddit, so that they can get out before the money runs dry.