Monochrome e-ink has a better resolution and contrast ratio than old-school LCD devices (I'm comparing my experiences with a Palm Pilot in the 1990s and an Onyx BOOX in the 2020s). LCD can refresh far faster, in the 100+ / 100s Hz range, where typical e-ink refresh rates in my experience have been in the single-digit to low-double-digit Hz range (video is doable but far from ideal).
E-ink also displays quite nicely with a "frontlight", which brightens the background (whiter whites) without washing out the foreground (print/ink). Illuminated LCD displays tend to wash out the dark fields, though I've not viewed e-paper directly and cannot speak to that.
TFA is describing a far higher e-ink refresh rate than I've experienced directly.
The thing about MIP is that the viewing angles are just not that amazing. I have had a Kindle and a Kobo, and they look like paper no matter how I hold them. My Playdate however needs to be positioned at a pretty specific angle with respec to the light to get the best contrast.