higher energy density
> (or electrolytics even)
no risk of drying up. Also, higher energy density, especially for small parts.
Digital was also the new expensive hotness, and putting in a tant wasn't going to be a big fraction of BOM cost.
These days my understanding is that ceramics and non-tantalum electrolytics have gotten good enough to replace most tantalum uses, and between that, the expense, the slavery, the exploding, and the environmental damage, they're less common than they once were.
The problem boils down to wanting to take power from AC in a sin squared wave, and outputting it at a constant rate. So you need storage of the integrated difference.
Therefore the energy storage required is the energy used in a quarter of a full cycle of the original AC.
For a 500 watt PC power supply running on 60 Hz, the storage is 2 Joules, which at an energy density of 2 Joules/gram gives you a capacitor of about 1 gram or 0.5 cubic centimetres.
Ie. The capacitor requirements for a desktop PC power supply can be as low as the size of a pea, if the design is right.
Typically they're far larger for other reasons - usually to simplify the design
I'm hoping for other superlattice materials to become available.