Both Tapo and Kasa will likely have a supported device of more than 5 years - given standard economic conditions - since they are still actively developing and delivering new products.
Kasa Legacy Devices. As far as security - although the Kasa devices have little in the way of security at the LAN level, they are still protected by the security embedded and implemented by you in your router (i.e., WPA2, AES encryption). For a plug/switch/light bulb that is fairly good.
Kasa Matter devices. These new devices utilize the same protocol as the Tapo devices - including security.
Tapo. Tapo does use secure login techniques as well as (during operation) message-by-message AES encryption. They are also VERY fast and work VERY well. The community implementation does not have the bells-and-whistles that the Kasa Integration has but it can be improved with improvement requests to the developer (me).
