I don't think either of you are wrong. The parent's assertion is that we've known this for almost a decade. BERT was highly usable for classification and sentiment analysis a whopping 9 years ago, despite being less than 0.5B parameters large. Similar-scale models like FLAN-T5 showed that it could be improved without substantially scaling up.
Today, we're extremely spoiled by trillion parameter-scale models. Our conceptualization of vibe coding relies on wasteful tool-calling paradigms, the one-size-fits-all mentality of LLMs is part of the marketing blitz to make people buy more tokens. It's lazy on the part of frontier labs, but also wastes electricity, time and money.