The main page (https://ravynos.com/) expresses the philosophy of ravynOS:
"We love macOS, but we’re not a fan of the ever-closing hardware and ecosystem. So, we are creating ravynOS — an OS aimed to provide the finesse of macOS with the freedom of FreeBSD."
rayvnOS seems to be designed for people who love macOS, particularly its interface, its UI guidelines, and its ecosystem of applications, but who do not like the direction that Apple has moved toward under Tim Cook (soldered RAM, limited and inflexible hardware choices, notarization, iOS-influenced interface changes, increased pushiness with advertising Apple's subscription services, etc.) and who would be unhappy with either Windows or the Linux desktop.
Speaking for myself, I used to daily-drive Macs from 2006 through 2021, but I now daily-drive PCs running Windows due primarily to the lack of upgradable RAM in ARM Macs. I'm not a big fan of Windows, but I need some proprietary software packages such as Microsoft Office. This makes switching to desktop Linux difficult.
It would be awesome using what is essentially a community-driven clone of macOS, where I could continue using a Mac-like operating system without needing to worry about Apple's future directions.
On the Unix side of things, I believe the decision to base ravynOS on FreeBSD rather than on Linux may make migrating from macOS to ravynOS easier, since macOS is based on a hybrid Mach/BSD kernel, and since many of the command-line tools that ship with macOS are from the BSDs. This is known as Darwin. It's not that a Mac clone can't be built on top of Linux, but FreeBSD is closer to Darwin than Linux is.