“The market research you find out there is typically just going to be very high level and you're going to have to cut it down. If you have great analytics on your platform you can learn enough about your consumers to figure out what segmentation actually matters — like what your SAM should be.”

Triangulate real SAM from your own product analytics, not market research

Don't trust top-line market research alone. Combine it with your own analytics on who actually uses and pays, then segment by the variables (geography, demo, commitment) that meaningfully change serviceability. SAM is triangulated, not looked up.