Harrison Ford has a long history of absolutely not buying into the mythology of Star Wars, and that history has been consistently entertaining over the years.
Case in point:
Roughly six years ago he hilariously told Reddit he didn't care whether or not Han Solo shot first in the long-debated Greedo scene in the original Star Wars. Now he's showing a similar level of disdain for new debate among Star Wars fans: Whether or not Han Solo's return in signified he was a "Force ghost" or whether the whole scene was just a figment of Ben Solo/Kylo Ren's imagination.
"Don't tell anyone," he continued. "I'm not talking loud enough for your recorder. I have no (expletive) idea what a Force ghost is. And I don't care!"
Which is exactly the response you would expect from Harrison Ford. His ability to continually skewer the need of fans to debate the granular details of every aspect of Star Wars is pure magic. Long may it continue.