Why is everyone pretending they know the difficulty in 2 months? I have checked my crystal ball and it turns out difficulty only increases ~20% per change as opposed to the pessimistic 30% rate which most calculators have adopted. This means everyone will still reach positive roi even with the delays.

In all seriousness you can't hold BA accountable for not guaranteeing a profit (according to your calculations which are 99% wrong).

You can however hold them accountable to deliver hardware that meets advertised specs. Delays are unfortunate but not uncommon (Historically just about every asic manufacturer has experienced delays).