I can confirm it from our testsuite run:

----
type=PROCTITLE msg=audit(03/01/2021 12:15:24.538:440) : proctitle=install -d -m 755 -o openvswitch -g hugetlbfs /var/run/openvswitch 
type=PATH msg=audit(03/01/2021 12:15:24.538:440) : item=0 name=(null) inode=1153 dev=00:1a mode=dir,700 ouid=openvswitch ogid=hugetlbfs rdev=00:00 obj=system_u:object_r:openvswitch_var_run_t:s0 nametype=NORMAL cap_fp=none cap_fi=none cap_fe=0 cap_fver=0 cap_frootid=0 
type=CWD msg=audit(03/01/2021 12:15:24.538:440) : cwd=/run 
type=SYSCALL msg=audit(03/01/2021 12:15:24.538:440) : arch=x86_64 syscall=fchmod success=yes exit=0 a0=0x5 a1=0755 a2=0x0 a3=0x1000 items=1 ppid=30091 pid=30140 auid=unset uid=root gid=root euid=root suid=root fsuid=root egid=root sgid=root fsgid=root tty=(none) ses=unset comm=install exe=/usr/bin/install subj=system_u:system_r:openvswitch_t:s0 key=(null) 
type=AVC msg=audit(03/01/2021 12:15:24.538:440) : avc:  denied  { fsetid } for  pid=30140 comm=install capability=fsetid  scontext=system_u:system_r:openvswitch_t:s0 tcontext=system_u:system_r:openvswitch_t:s0 tclass=capability permissive=0 
type=AVC msg=audit(03/01/2021 12:15:24.538:440) : avc:  denied  { fsetid } for  pid=30140 comm=install capability=fsetid  scontext=system_u:system_r:openvswitch_t:s0 tcontext=system_u:system_r:openvswitch_t:s0 tclass=capability permissive=0 

I haven't managed though which process executes the install command. Can the runtime directory be created using systemd means in the service unit file?

Switching the component to openswitch for the maintainer to assess.

Related bzs:
https://bugzilla.redhat.com/show_bug.cgi?id=1908527
https://bugzilla.redhat.com/show_bug.cgi?id=1844198

We did use systemd to create the runtime directory, at one point.  However, systemd behavior was changed and the runtime directory permissions
were being modified underneath us in a manner that we couldn't use (because we need to select between group ID based on system configuration).

Systemd folks refused to restore the old behavior, so we went back to the scripts managing the creation of the runtime directory (which is why
I guess we now need the fsetid permission - we are using a secondary group ID for the runtime dir).

Still happening in Fedora 34:

SELinux is preventing install from using the fsetid capability.

*****  Plugin catchall (100. confidence) suggests   **************************

If you believe that install should have the fsetid capability by default.
Then you should report this as a bug.
You can generate a local policy module to allow this access.
Do
allow this access for now by executing:
# ausearch -c 'install' --raw | audit2allow -M my-install
# semodule -X 300 -i my-install.pp

Additional Information:
Source Context                system_u:system_r:openvswitch_t:s0
Target Context                system_u:system_r:openvswitch_t:s0
Target Objects                Unknown [ capability ]
Source                        install
Source Path                   install
Port                          <Unknown>
Host                          chainsaw.msnomer.com
Source RPM Packages           
Target RPM Packages           
SELinux Policy RPM            selinux-policy-targeted-34.6-1.fc34.noarch
Local Policy RPM              selinux-policy-targeted-34.6-1.fc34.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     chainsaw.msnomer.com
Platform                      Linux chainsaw.msnomer.com 5.11.19-300.fc34.x86_64
                              #1 SMP Fri May 7 14:17:15 UTC 2021 x86_64 x86_64
Alert Count                   18
First Seen                    2021-05-02 15:33:32 EDT
Last Seen                     2021-05-15 10:27:20 EDT
Local ID                      c1e5c2a4-b67c-444a-af9a-724e95df5d40

Raw Audit Messages
type=AVC msg=audit(1621088840.853:181): avc:  denied  { fsetid } for  pid=934 comm="install" capability=4  scontext=system_u:system_r:openvswitch_t:s0 tcontext=system_u:system_r:openvswitch_t:s0 tclass=capability permissive=0


Hash: install,openvswitch_t,openvswitch_t,capability,fsetid

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