I would have expected better especially from Harvard, it's already known why. Subjective time is measured in terms of biological impact events. Basically the more novel experiences you have the slower time seems to pass for you, the less novel (interesting) stuff you do the faster time passes because there's no markers. This stuff has been known for literally decades now.
Anecdotally, I've been sitting in the same house for 20 months of the pandemic and have a diminished sense of time, and while in that time I've taken up music and new instruments, written volumes, transformed physically (weight loss), kept up regular highly intense physical hobbies, added and removed clients/jobs, worked in vastly different fields.
However, I've always pursued novelty, and I'd wonder if this accepted explanation would indicate that the brain is now just bored of novelty, or if something about these things were not sufficiently novel experiences, and where does that sufficiency land?