So, I attempt to disassemble the strut to see what's wrong. And the result: couldn't find anything wrong aside from some minor paint chipping of the mount. The mount was still all intact, and the bearing could still rotate freely.
It was apparent trying to rotate the strut (while installed) that there was some binding causing the spring to move a bit in the strut seat. Upon removal of the spring from the strut, I noticed the bottom of the spring isolator had some deterioration and developed a minor hole - guess that was due to the friction.
I think the problem was just incorrect (as in, excessive) torque which put too much pressure on the mount & caused some paint to chip which might've interfered with smooth rotation of the bearing.
I took everything apart, and since everything still looked normal, I reassembled the strut & made sure I was using the right torque specs as detailed in the FSM. After the removal, disassembly, simple cleaning, reassembly, & reinstallation, I don't get the clicking anymore but it remains to be seen if it will return.
Top & bottom of mount had no play or loose parts:
Bearing was alright:
The sandwich piece (between the mount and the upper spring seat) had some minor paint chipping, which probably caused the binding:
