That would actually be incredibly surprising, shocking, in fact. There's really only so much work that can be done inspecting and refurbishing the rocket stages, they only have so many systems. They are precisely the opposite sort of beasts as the Space Shuttles which were some of the most complicated systems ever created by mankind. The Falcon 9 boosters are pretty much just engines, propellant tanks, avionics, and some miscellaneous bits. There's just not a ton to inspect and not a ton that can go wrong. More importantly, the vast majority of the cost of the vehicle is in the engines and tanks. The tanks are unlikely to degrade from launch to launch and are practically binary in their serviceability (they either work or they don't). Engines are incredibly expensive to manufacture and realistically the amount of inspection work that would need to be done to match that cost is just mind-boggling, and there's no good reason to imagine they'd need to do more than bore scoping. Especially since at this point if they find a potentially problematic engine, they just unbolt it and bolt on a brand new one. This increases costs a bit, of course, but it still saves a tremendous amount of costs. If the incremental flight cost of a first stage goes from the full manufacturing cost down to the cost of an engine or two plus recovery, inspection, and refurbishment, that's at a minimum tens of millions of dollars saved.