Distrobox is underappreciated as hell, no surprise that vanillaOS, and alikes are getting so popular right now.
I have a laptop with opensuse, great, great distro, performance is awesome, very stable and resilient, running the latest KDE, for most apps, I have flatpak in user mode, so I don't write anything in my root directory, nothing runs as sudo.
But opensuse has a fatal flaw, ~~it's not arch linux~~, software availability is not exceptional, sometimes you miss a thing, or the software you relie on, doesn't work, or it's broken because it won't support suse properly. That's where distrobox comes in, using it you can create a container distro and have you software in there, hell, you could even make multiple containers for different uses, like a development container with vs code, and the gazillion libraries and dev packages inside without having to worry about bloating the main system, or a gaming container with lutris, wine, all it's 32 bit libraries and dependencies without mixing them with the host system, like I do, or perhaps you can have a container with davinci resolve, or other program that ~~still~~ has a windows-like installer that either works, or breaks your entire system every time you try it on a new distro, possibilities and almost endless! And even better, no performance penalty!
The coolest thing about distrobox is for sure the container-userland integration, for example, if your app inside distrobox is able to use xdg desktop portal, you can do cool stuff like screen capture, file picking, and actually having the right theming(if you have a copy of your theme under your home of course), all with the Host's portal! Even fonts sync with the host!
Sadly, distrobox is not flowless, you can't really use it with things that depend on deeper system integration, for example, waydroid, which needs to have a service running as root on the kernel for it to actually work, so using it on distros like opensuse or your average independent Linux based operating system, [insert cool, or clever word]OS that you and other 6 people on the entire globe love (for some reason) remains impossible without proper support.