The problems with the alternative - interviewing based on problem solving and coding challenges are:
1) For the most part it doesn't work. Companies like Google, that have reflected on and assessed their own interviewing success, have come to the conclusion that there is little correlation between how well people interviewed in this style do on the interview vs how well they perform on the job. This is a pretty low bar to beat!
2) If you are interviewing for 10-20-30 year senior with a track record of success and adding value, how can you possibly hope to assess that via problem based challenges, especially if conducted by a less senior developer who doesn't themself have the skill set and track record you are hiring for? How do you know if the person just talks a good game and can throw around high level concepts, or can actually deliver?
I do think there is some value to problem solving as a small part of the interview process, but certainly not if this comes at the expense of ignoring the candidate's actual experience and accomplishments which is the best indication of what they are capable of.