Although you can download the traditional Dev parts,
It looks like Android is currently promoting the use of Android Studio as the master management app… Within Android Studio you can download specific SDKs for your target platforms and more.
I also generally install from Android, but if you only want basic functionality it may not matter where you get utilities like adb, and yes it’s convenient that if you install from openSUSE, your tools can be updated automatically.
If you instead prefer to install from Android,
Links to download Android Studio as well as the CLI tools are on this page
Doesn’t your referenced page say that builds are still actively done and were successful against all platforms but for some reason disabled placing into all repositories (except Factory_z which was blocked for some reason)?
In any case, for anyone who looks for a usable adb (I can’t opine about others in the Android Tools), any working binary from any similar architecture system can be copied to another, and it will “just work.” No real install needed. And, I don’t know for sure but the code may not have changed since… forever… I don’t know if it has ever changed since earliest days.
As for finding in TW…
Looks like the entire Android Tools package is not in the TW repo, which is why it can’t be found (but can at software.opensuse.org).
So, simple reason why a zypper search won’t find it.
Yes, I can’t find any reference to it every being submitted to Factory/Tumbleweed. I would guess it’s some transient issue with a deleted build in the hardware repo, a sync being done and it was temporarily deleted…
@OP, please show your repository list to confirm the hardware repo is present… it could also be the repo flip issue yast2 vs rpm-md…