Point trying to make? Not that complicated, really.
You stated that discussions about TCAS or TCAS II don't apply, as this is a private pilot forum.
Point is that while those are the best options and most other lesser systems are a waste, even the best systems have no assurance. Whereas even the best systems haven't prevented incidents, don't put too much faith in the cheap ones, either. Especially one's with limited and unclear display information.
Pilots who use TCAS to find traffic are much like pilots who use radios to find traffic for them. Call out and ask if there's any traffic out there...it's a stupid call, and a lazy one. Much like "got 'em on TCAS."
Not that complicated at all. But you're right, there is traffic out there.
TPAS and the other cheap efforts at TCAS aren't really worthy of one's time or effort or expense, are more prone to errors, to creating a distraction, and to confusion, and offer too little information in a non-intuitive format such that they contribute little to situational awareness.
That, and some examples were given. Clear?