Debugging is more than just attaching a debugger to a running program. Identifying the correct root cause is a skill. In addition, the complexity of distributed systems and multi-language stacks makes debugging even harder.
The key to a long career in software is the ability to build large systems. Large-scale systems cannot be created on a single machine using a single programming language. Hence one has to evolve into a generalist engineer to lead such efforts. Irrespective of role, understanding complexity and the ability to navigate it during production firefighting is a growth accelerator in the industry.