Something very strange happens in OBS. The snapd for Tumbleweed is built against Tumbleweed version of the selinux-policy. In the log it can be clearly seen:
...
[ 8s] [242/248] cumulate selinux-policy-20251006-1.1
...
[ 328s] Processing files: snapd-selinux-2.71-1.27.noarch
[ 328s] Provides: snapd-selinux = 2.71-1.27
[ 328s] Requires(interp): /bin/sh /bin/sh /bin/sh /bin/sh /bin/sh
[ 328s] Requires(rpmlib): rpmlib(CompressedFileNames) <= 3.0.4-1 rpmlib(FileDigests) <= 4.6.0-1 rpmlib(PayloadFilesHavePrefix) <= 4.0-1
[ 328s] Requires(pre): /bin/sh
[ 328s] Requires(post): /bin/sh libselinux-utils policycoreutils policycoreutils-python-utils selinux-policy-base >= 20251006-1.1
but looking at the downloaded package, it suddenly requires the selinux-policy 20251008 which is only available in Factory, not in Tumbleweed.
andrei@tumbleweed:~> rpm -qf /usr/lib/rpm/macros.d/macros.selinux-policy
selinux-policy-20251006-1.1.noarch
andrei@tumbleweed:~> rpm -q --requires -p snapd-selinux-2.71-1.27.noarch.rpm | grep selinux
warning: snapd-selinux-2.71-1.27.noarch.rpm: Header V3 RSA/SHA256 Signature, key ID ed340235: NOKEY
libselinux-utils
selinux-policy >= 20251008-2.1
selinux-policy-base >= 20251008-2.1
andrei@tumbleweed:~>
It looks almost as if OBS mixed up builds for Tumbleweed and Factory.
That is beyond my OBS-fu. It needs proper bug report.