Well, tantalums are very high performance for their size, you can't beat that. And according to manufacturers they should not wear out (even though we all know old tantalums do appear to explode spectacularly - maybe new power supplies put more surge/ripple current over them than older power supplies).

And, tantalums are quite different in their specs than electrolytics. In some linear regulator bypass applications, you'd either need a 1uF tantalum or 25uF electrolytic to reach similar performance.

Having said that, if you look at generic tantalum specs and try to find matching or better electrolytics, it should work. But the electrolytics can be bigger than tantalums. Also, if you need certain ripple current handling ability or effective series resistance, the capacitor size is somewhat same, since you could have that same performance with either 68uF/16V cap or 47uF/25V cap. In other words, given two caps with same capacitance rating but different voltage rating, the one with higher voltage rating performs better.

I did notice that if the motherboard has 10uF tantalums, you can't even get 10uF Panasonic FM caps as the smallest capacitance is 22uF. Then just increase the capacitance.
I am not so aware of these solid electrolytic caps.

If the capacitances are quite small, around 10uF to 22uF, consider ceramic capacitors as well, but the more you put voltage on them, their capacitance value could be as small as 50% of the rated capacitance.

Manufacturer literature recommends polymer caps for tantalum replacement.