My point is that DEBUG level logging is (hopefully!) not on by default, and that this is what it makes the production log volume manageable.
My experience has been that 1 customer-facing byte tends to generate something like ~10 DEBUG-level telemetry bytes. This level of request amplification can't be feasibly sustained at nontrivial request volumes, your logging infrastructure would dwarf your production infrastructure.
Or, to flip that around, if you take a program that produces a manageable amount of INFO logs, and change some of those INFOs to DEBUGs, how does that suddenly become unmanageable?