As somebody in an ML Engineering role, i.e. somebody who could be asked to either fix the logging infrastructure or build some models, I would have agreed with this.

But even in this day and age with ML being the new hotness, you will find people who are quite happy to work on infrastructure and don't have a huge amount of interest in training models themselves, and it is probably a lot easier to hire them than people who can do both, and you may get better results from actual specialists.