All the comments excusing the RAM usage "because high-resolution screens require pixels" are missing the fact that there's this thing called GPU memory. Which is where pixels data should be. There's no way you need to store fullscreen 4K images for a weather app on anything else than the GPU: use scalable icons, render them on the GPU. No need to use actual RAM: the GPUs have had their own RAM since times immemorial and GPU rendering is a thing too.
Lots of iGPUs just end up being backed by system memory. But even then, this is a ridiculous hand wavy excuse. A 4000x2000 RGBA buffer is 32MB. That only explains 2.7% of the weather app's devastating memory footprint.
They don't want you to remember that Windows XP's minimum system requirements specified 64MB of RAM. This weather app uses 20 times more memory than an entire operating system from 25 years ago.
