OPTX interview questions

Initial interview with hiring manager was pleasant. He then gave me a homework assignment with a little over 24 hours to do it (the HM later kind of alluded to others maybe getting more time which seemed a little unfair). Had a brief phone call to go over my results with the HM and was told I would have a meeting with CEOs the next day to ask them about the company and get a feel for the culture, etc. However, in the meeting, the HM told me to present the results of the homework analysis to them, which I had no idea I would be doing so was not prepared. Afterwards I was told I would have my questions answered later about the job that I asked in the meeting, but there was zero communication. After a week or two, I emailed the HM to check in and at least see if they had passed on me for the job. He never responded. Not even a "thanks, but no thanks" email. The company basically ghosted me after 3 interviews.