While I don’t pretend to have any inside knowledge re the recent TCAS warnings, I can’t help but feel it may be more to do with inexperience and a basic understanding of just how TCAS works.
Both recent incidents have occurred on climb / descent. Traffic or targets just don’t suddenly appear. If you have operated in some of the very busy environments overseas you soon become intimate with TCAS and how it works, including some of it’s limitations, especially operational techniques which will cause hard warnings.
Basic airmanship will in most cases warn you of the possibility of an imminent hard warning, enabling the crew to adjust the climb or descent rates to avoid this sort of incident.
Current software may have sorted out the so-called “Dallas Bump” when a TCAS warning occurred when one aircraft was on a high rate of descent and an aircraft climbing up on the reciprocal track could cause a warning even though both aircraft were separated by 1000’ or more.
On all the glass cockpit aircraft I have flown the so called targets were clearly visible enabling crew to adjust their ROC or ROD.
Perhaps we should be looking at operating techniques rather than blaming the system.