It's because it always wants to load the always-sink module:

# Extra modules can be loaded here. Setup in default.pa can be moved here
context.exec = [
    { path = "pactl"        args = "load-module module-always-sink" }
    #{ path = "pactl"        args = "load-module module-switch-on-connect" }
    #{ path = "/usr/bin/sh"  args = "~/.config/pipewire/default.pw" }
]

Maybe we should require pulseaudio-tools as a runtime dependency for pipewire-pulse.

> Mar 04 07:48:12 t590 wireplumber[2205]: Failed to set scheduler settings: Operation not permitted

This is because the user does not have the right permissions to set the nice level of wireplumber. It's harmless but I don't know
of a good way to add the permissions.

[test@rhel-9 ~]$ systemctl --user status pipewire-pulse.service 
● pipewire-pulse.service - PipeWire PulseAudio
     Loaded: loaded (/usr/lib/systemd/user/pipewire-pulse.service; enabled; ve>
     Active: active (running) since Mon 2022-03-14 08:15:55 CET; 2min 10s ago
TriggeredBy: ● pipewire-pulse.socket
   Main PID: 895 (pipewire-pulse)
      Tasks: 2 (limit: 24826)
     Memory: 4.1M
        CPU: 17ms
     CGroup: /user.slice/user-1000.slice/user/session.slice/pipew>
             └─895 /usr/bin/pipewire-pulse

Mar 14 08:15:55 rhel-9 systemd[848]: Started PipeWire PulseAudio.
Mar 14 08:15:56 rhel-9 pipewire-pulse[1039]: 536870912
[test@rhel-9 ~]$ rpm -q pipewire
pipewire-0.3.47-2.el9_0.x86_64

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (new packages: pipewire), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2022:2328