how does "as" function in this sentence? Does the sentence not make sense if "as" is omitted?

Native speaker’s answer
Rebecca
It would make sense without "as!" But, here, "as" functions as a comparative word. So not "as loud" compared to something else. Here, the comparison implies "normal" or "usual." Ex: If you use your left hand, you won't draw as well since you're right-handed. Ex: She hasn't practiced piano as much this week. => compared to the previous week.