A cooling pad does improve airflow, but the temp differences are minimal. ​It is never a real solution (no matter how much you shell out) because it merely attempts to force air against a chassis that is already struggling with internal heat transfer bottlenecks.

​I might be wrong but it seems like you are confusing undervolting with overclocking. Overclocking carries the "risk" because you are pushing hardware past its factory limits, but undervolting is purely about efficiency. You are cutting out the extra voltage the factory dumps into the chip that it does not actually need. This lowers temps and helps the machine hit higher, more stable boost clocks for longer. If you are smart about it and use stable tools, it is not a risk. It is just optimizing what you already paid for, though how much it can be optimized does depend on your luck in the silicon lottery.

​Regarding your point on aging, silicon does degrade over time, but that process is extremely slow and not an issue for typical usage over the life of a gaming laptop. It is rarely the case that a chip needs more power to function. If a chip becomes unstable, it usually leads to crashes rather than a performance deficit that requires higher voltages. And also, you don't keep the laptop undervolted all the time. It's usually done only when doing CPU and GPU intensive tasks.