Without digging in too much, my guess is that rviz is launched after the bridge and the bridge doesn’t support latching (or transient local durability for ROS 2), see:
The right fix is to support latching in the ros1_bridge, but there was some discussion on how to best support that and it was never resolved.
The other option would be to modift tf2 in ROS 2 to publish /tf_static periodically.