Powerbombs
 

Why doesnt anyone appart from Batista use a powerbomb anymore?

Because it's not scripted.

You actually answered your own question. Vince doesn't like it when people use other people's finishers. That's why Juvy doesn't use the 450 and why London doesn't do the SSP.

UT and JBL are, of course, above the law, and use powerbombs from time to time still, but they're the only exceptions I can think of.

You'll see them as a counter once in awhile too, ala Nitro/Mysterio in the tag match.