They largely have now, archinstall.
It's still text based/TUI but it's pretty simple and intuitive, anyone already familiar with installing a Linux distro (especially any sort of -server variant) will be comfortable with the archinstall script.
Regarding why Arch doesn't "invest" in a graphical installer, it's worth mentioning that Arch's installation image has a different design philosophy than most installation media.
The image is a fully functional arch environment that copies the entirety of its contents to RAM on boot, giving you special installation opportunities such as the ability to install Arch to the same flash drive that booted the installer. Having no graphical dependencies lets this image remain small enough to pull this off, as well as allowing for fully remote installations over SSH out of the box, since archinstall is a TUI.
I don't have a way to quickly around to check, but I thought the arch install media used squashfs? In which case I wouldn't have thought it was safe to blow away the backing store.
To be fair, thats not _generally_ the audience we tend to think about when we talk about the enshittification of Windows. We're usually talking regular consumers / computer users and "gamers" the latter of which is a wide range of people that can fend for themselves with instructions to people that cannot.
I'd direct them to something like Bazzite (Immutable), or CachyOS for staying arch-based but providing a GUI installer and tools, Endeavor OS, even Fedora, etc.