Aenghus
Explorer
I think superpowered wizards like Mordenkainen, Elminster and Raistlin provided aspirational figures for spellcasters that other classes lacked. D&D had ubernpcs long before White Wolf. Named spells are the most common in-game branding in D&D.
Also for a long time it's been easier to make challenging BBEGs with wizards. Something of a chicken and egg situation, in that making wizard NPCs more challenging to fight trickles down more power to PC wizards, who do everything they can to aquire the most broken abilities of the bad guys they are fighting.
The power level wizard players can aspire to has steadily grown with the accumulation of thousands of spells, the most powerful of which slowly bump up the power curve. First TSR and now WotC have produced mechanics for their ubernpcs, some of which have fallen into the eager hands of players who unsuprisingly want them a lot, and are willing to pay for them.
Also for a long time it's been easier to make challenging BBEGs with wizards. Something of a chicken and egg situation, in that making wizard NPCs more challenging to fight trickles down more power to PC wizards, who do everything they can to aquire the most broken abilities of the bad guys they are fighting.
The power level wizard players can aspire to has steadily grown with the accumulation of thousands of spells, the most powerful of which slowly bump up the power curve. First TSR and now WotC have produced mechanics for their ubernpcs, some of which have fallen into the eager hands of players who unsuprisingly want them a lot, and are willing to pay for them.