This exactly - no reason why you couldn't ifdef everything that is debug only, if your team is consistent with it from the very start. Backfilling existing cod

This exactly - no reason why you couldn't ifdef everything that is debug only, if your team is consistent with it from the very start. Backfilling existing code with ifdefs and dealing with compile breaks and other more weird things can be intimidating, time consuming, with hard to define ROI, so I can empathize if someone doesn't do it.