It's because of all the testosterone on the internet
Inexperienced males usually group into tribes and cannot visualize being in another tribe. More experienced men have the wisdom and individuality to pick and choose the best of each tribe.
While they're both coprocessors, their purpose and flexibility are totally different.
A TPM is a specialized processor (usually on a separate chip) that's dedicated to a single purpose: authenticating the trustworthiness of a piece of hardware. That's all it does. It stores credentials and validates them. It runs a standardized set of functions with a standardized command protocol.
A Secure Enclave is a secured section of a CPU (usually onboard as either an actual or virtual coprocessor) that is general purpose and can be programmed to do any function that you wish to be secure. These are usually proprietary functions. For example, in an iPhone it's used to store and validate fingerprints, and to setup and talk to the NFC Secure Element for Apple Pay. In the future, it could be programmed to do more things.