$50 is a number for LEO (Low-earth orbit). $/kg to a Moon orbit (or flyby) might be significantly more expensive. Not only that, because it is further so it needs more fuel, but also it is a few days trip which would need a bunch more kilos in provisioning food, water and other things. So yeah, unfortunately not that cheap to have a honeyMoon in the moon (heh)

There is a lot of possibilities to make a trip to the moon cheaper though. If we make LEO that cheap, we can build a lot of infrastructure in the space that would make the tourism to moon more affordable. Like keeping a few starships always in orbit as some kind of space-hotel-metro system.

This will probably take a few more decades, though.

Only if you don't care about coming back!