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High speed design requires that there not be stubs in the via which could create signal integrity issues due to reflections. Thus, uVia (micro-via), buried via, blind via and back drilled through hole via can all be used in place of normal through hole via.
Now the question is, are all these via types only relevant to high speed board design or they are useful elsewhere as well?
Back-drilled vias are typically relevant for high-speed designs only. That's because they are relatively expensive and don't offer any other significant advantages apart from reducing signal integrity issues caused by via stubs.
The other types are usually used in high-density designs to free up space for routing/placement. Of course, a high-density design could also be a high-speed design. In this case the other types provide similar advantages as back-drilled vias (no or smaller via stub).
Not just for high speed.
If you have a very fine pitched BGA case IC with large amount of pins, it will be difficult to "fan out" the signals away from the IC.
However, such large ICs tend to be intended for high speed signals, so they may relate.
An interesting twist is, as there is pressure to make everything smaller, and even if fast signals benefit from ICs being packaged into small packages with small pitch, it also means you need to use more tricks that make the PCB harder and more expensive to manufacture. Such as more layers to be able to route the signals, and microvias, buried vias, blind vias. And backdrilled vias if preventing stubs is important for very high speed signals.
