Ya, because we wouldn't want interplay between historic 20s spanish revival work and a more modernist approach. That would be way too progressive and might actually (gasp!) create something that is artistically and architecturally interesting. It might actually (no!! noooo!!) allow San Antonio to gain recognition for being willing to allow the forms and materials of 2010 to dance alongside the prevailing beauty of 1920.
We wouldn't want our artistic beacon of the city to take any risks or make any striking, bold statement on the reinterpretation of a classic form...