Re: QLC? It's not the one for me
You are a bit confused about the distinction between analog and digital. At the nanoscale, its all analog (and at femtoscale it's all digitial again that's a bit deep for this post, just google quantum number). Those rather alarmingly analog-looking traces are coerced into representing digital values via thresholding and latching effects. Ever seen an ether bird? It's a bit like that. A wind-up clock is like that too: the spring is analog but the tick is digital.
Multilevel cells likewise rely on thresholding and latching effects, there is just more than a single threshold value. Still digital by nature, just like single level cells, Maybe the threshold voltages or whatever get closer together in multi-level and risk more errors, or maybe not. Single level logic gets shrunk and packed together as tightly as possible, which also increases the risk of error. Given the same number of bits stored in the same area, it is far from clear that multi-level cells have the higher risk of error, it may be just the opposite.