Aha! UX Designer interview questions

The interview process was multi step like most companies: 1- HR Screening 2- UX Manager Screening 3- Product Manager Screening 4- Take Home Assignment The interview process was average. Slightly challenging, but nothing crazy. The part where I was declined was the very last part --The take home challenge. I was asked to spend three hours on this challenge. The challenge was based around working on a product problem for the Aha product ecosystem. Im not a fan of design challenges really, they are outdated and many comprehensive studies show that, but I did complete the challenge anyways and provided a high level of detail into my design approach. After taking most of my afternoon to complete the challenge, I was rejected. The reason for rejection was very vague. Seems like something to be caught in an HR screening, but it wasn't. So this tells me either they didn't screen me enough or they knew I wasn't what they wanted, but wanted to have me do the design challenge just for pure entertainment. All that being said, I thanked the hiring manager and asked for feedback after being rejected. At this point I was ghosted, which felt pretty rude considering how much time I dumped into the whole process. While I did enjoy the interview experience even though I was rejected from an offer, I'd expect at least a couple bullet points of feedback after spending close to 6 hours total on this whole process.