Well, I would wonder about that latency, given the latency in the GPS position.
TCAS does not use GPS at all.
Altitude is barometric.
Range and range rate are calculated from interrogation pings.
Direction is highly approximate and for pilot situational awareness only.
Depending on the system, they handle they track and handle the threats differently, hence, there is a proprietary factor as well.
TCAS is a specific implementation of ACAS. TCAS algorithms are standardised with the intention that there should be no variation between manufacturers.