>in most cases doctors have many, many thousands of hours under their belt in training before still needing to study a ton to pass their boards
The difference is that what the doctors put so much time into learning can actually be quite useful for their job. The vast majority of competitive coding stuff isn't. Interview procedures based around it completely fail to assess some of the most important abilities in software engineering, like API design. As anyone who's ever used any of Google's open source libraries would have noticed, hiring people who do well at competitive coding problems is no guarantee they'll be able to produce decent software.
The difference is that what the doctors put so much time into learning can actually be quite useful for their job. The vast majority of competitive coding stuff isn't. Interview procedures based around it completely fail to assess some of the most important abilities in software engineering, like API design. As anyone who's ever used any of Google's open source libraries would have noticed, hiring people who do well at competitive coding problems is no guarantee they'll be able to produce decent software.