Paul covers off, in a lot more detail than this description, the top three reasons why he thinks that Container Queries are not needed. This article, thankfully, sparked further conversations which is awesome.
Earlier last month, Ethan wrote about the need for container queries, a request that is frequently raised in any discussion about the future of responsive design. Ethan’s article is well worth a read, especially if you’re unfamiliar with the issue, but here’s a brief summary: the dimensions of the viewport are a poor proxy for judging layout requirements for components that can exist in a variety of contexts. If we could query the dimensions of a component’s parent container instead, our layouts would be more robust, and our code easier to maintain.An excerpt from Questioning Container Queries