What you lose when you move away from text logs is not any real benefit; what you lose is the illusion of control you have with text logs.

Text logs can be corrupted, text logs can be made unusable, you need a ton of domain-specific knowledge to even begin to make sense of text logs, etc.

But there's always a sense that, if you had the time, you could still personally extract meaning from them. With binary logs, you couldn't personally sit there and read them out line by line.

The issue is psychology, not pragmatism, and that's why text logs have been so sticky for so long.