To be clear, the Transporter missions are different from the standard list price ones. You can get your own Falcon 9 ride for $70M, and that’s what it’ll actually cost if you use the standard payload adapter and don’t require any extra services.
But the Transporter missions are priced by the kilogram. It’s a pretty good price–around $6000/kg instead of the $4000/kg for the full rocket. Not a bad premium for a rideshare.
SpaceX doesn’t always fill out the whole rocket, though. Out of the ~17 tons available, maybe they only sell a few tons. At 2.5 tons, they’re only making $15M.
At that level, it’s probably a loss or close to it. But as I mentioned, the whole point is to operate it like a bus that leaves on a regular schedule, so some of the value is in the fact that you can depend on a certain launch date and make plans around that.