Consider me confused. Isn’t quantizing a value, e.g. reducing the number of bits in an int, a form of discarding information from that value? Isn’t your comparison just about discarding information on another level (discarding entire values)?
I think the GP's point is, if you don't know what quantization is, the article gives the impression it consists of discarding some of the values, which is where the compression comes from. This is a good "0-th order" intuition, but quantization is a softening of this; instead of fully retaining or fully discarding a value, there is a sliding scale of how much information to discard. If you already know what quantization is, it's easy to see how discarding is a special case, but the article gives the impression discarding = quantization.
I think the GP's point is, if you don't know what quantization is, the article gives the impression it consists of discarding some of the values, which is where the compression comes from. This is a good "0-th order" intuition, but quantization is a softening of this; instead of fully retaining or fully discarding a value, there is a sliding scale of how much information to discard. If you already know what quantization is, it's easy to see how discarding is a special case, but the article gives the impression discarding = quantization.