Disorganised, egotistical and ignorant of an applicants time & effort. If you love 5 stage interviews, multiple hours of effort and radio silence - this is the one for you. I would say to this team: If you demand the 3+ hours of interviews and a multi-page case study from your prespective talent, the very least you could do is send through a real human email to let them know they will not be progressing.
Positive: every interaction with the main contact was polite and professional - they just need to seriously review their process.