I don’t like it, it’s another exercise in taking a functional website and ‘modernising’ it by making it look like a mobile app (i.e. the make it look attractive to kindergarten kids school of design).
For my own use cases it’s made it more annoying to get to the 7 day Canberra forecast, made the local radar harder to see, and I’m not noticing a link to the written ACT region forecast which I will want to look at in winter.


Screen reader. Like for blind people. Who need the screen read out to them. Verbally. By software. Whom the government should be considering while building digital services. See previous mention about “usability issues”.
I’m glad you consider yourself among the smart people. I haven’t worked with the designers on this particular project, but like most I’ve worked with before I would assume they’re also reasonably intelligent. They’ll understand, just like I’m sure you do, that a good interface is an intuitive one. We all have mental models of how we expect software to “feel”; how it should navigate, be structured, and just behave in general. Any time you break that model, you add friction as the user has to learn how your specific app behaves. Of course, there are sometimes good reasons to do so, but I would argue that the weather, which is generally considered a basic task, is not one of them. Therefore, updating their website to match common, modern, and well reasoned design patterns to make it more accessible to new users is reasonably justified.
That said, existing users of BoM already have a mental model of the website, and by updating it they’re breaking it. They’re essentially privileging the experience of new users and they should be careful to ensure the redesign is actually necessary. This is a trade off of all redesigns but, considering my previously mentioned issues with the old website, and their clear effort to maintain feature parity, I would argue that that is fair in this case.