I think audiophile is primarily a passion and frame of mind. When you are truly passionate to get the best possible sound achievable… and people think you are crazy.
Often the test is monetary. Because the percentage you are willing to commit to your passion is a legitimate gauge. So the idea that an audiophile is someone who’s system cost more than his automobile(s). This has been true for all of my life… even when my car was a used cheap Datsun 1200 and now with a contemporary 4Runner and Lexus in the garage.
It is about passion and commitment.
On the other hand there are audiophile components. These are built to exacting requirements where component costs are unimportant… sound quality is the only objective. These tend to start around $10K to $20K. So every aspect is optimized… the best… not cheapest subcomponents are used.
So, budding audiophiles seek out off brands, used audiophile equipment and off beat techniques to get the best sound they can.