hi i'm currently looking at some new cisco phone systems and something on the wish list is a click to open account on our intranet.
I've been advised to look into tapi so I wondered if this worked with teams so I could create and test a solution.
i cant find any sample code younger than 4 years old so also wondered if this is fading out with the newer wave of unified comms
The current trend in the unified comms is moving to proprietary interfaces. TAPI does not really have decent facilities to deal with the addition of chat and video channels anyway. While some vendors seem to be willing to keep supporting it for some time, most seem to be designing new API's from the ground up (Teams Graph, Cisco WebEx, Alcatel Rainbow,...)
Specifically to your question: no, Teams does not support TAPI and there seems to be no intention to ever do so. None of Microsoft previous UC solutions (Skype for Business, Lync, Office Communication Server) did either.
If you don't want to develop/test straight onto your production Cisco, you may be able to get a VM version of the PBX with a trial/temporary license for software development purposes through a Cisco partner.