After talking with a recruiter and the hiring manager (who told me that he perceived the "fit" was good), I was set up to go through 4 formal interviews: technical deep dive, problem solving, managerial journey, and pair programming. The job posting was taken off a day or two before my interview but I was not notified about it by Shopify, as they went through with the interview process. Afterwards, the feedback I received after my interviews was so immensely disconnected from my own experience during the interviews that I was just speechless while I was on the phone with the recruiter. My own assessment was that my problem solving interview could have gone better but the other ones were just fine. However, the interviewer who was supposed to assess my technical skills in approaching a problem (his own words) had his mind set on assessing my "business intelligence" skills without telling me about it, and the interviewer in pair programming was ticked off when i told him that i am not a software engineer (his words: "you said you're not a software engineer? let me write this down; it's important!"). I believe both of these interviewers were incorrectly assigned to their corresponding interviews, as the former didn't have the technical chops to assess my technical skills (and instead chose to focus on something else which was not even the objective of the interview) and the latter didn't even bother taking 30 seconds to skim over my resume before the interview to notice that i am not a software engineer (and i was not even applying for a software engineering position to begin with anyway!). Based on these meaningless feedbacks, I was offered a position that was two levels lower than what I had applied for just because "they all thought I would be a good fit at Shopify and they all want to work with me". In justifying this switcheroo, the recruiter tried to tell me that Shopify is a software company and that's why they want people with software engineering backgrounds (but I applied for a data science-related position, and most companies that do data science are software companies anyway) and that Shopify is as close to a merit-based company as possible, so I should be moving up in the hierarchy as fast as possible (am I supposed to risk my career based on these intangible unofficial words?). The overall feedback and the reasons behind it was just immensely insulting, and the entire thing was a complete waste of my time. This was something I would have expected from a third-rate, no-name company in the middle of nowhere, not from a company of Shopify's prestige.
My advice to future interviewees at Shopify is to clarify exactly what each interview (and each interviewer) wants from you at each step of the interview, lest they'll do another switcheroo on you as well. My advice to Shopify's technical interviewers is that if you think you're not qualified to assess someone, please sit it out and let someone else do it and that please take a minute to go over the candidate's resume before to familiarize yourself with him/her experience and background; just because you're in the position to ask the majority of the questions doesn't mean that you're all-knowing. Shopify's HR team, please connect with your technical folks; these experiences will give Shopify a bad reputation.