Technically, yes the Neo-Geo does beat the GBA in almost all areas except maybe CPU speed
GFX
Neo-Geo- 320 x 224 res with 4,096 from 65k colours in game
GBA - 240x160 res with 511 from 32k colours in game
MEMORY
Neo-Geo - 7MB RAM and 512k VRAM + 64k SRAM
GBA - ~300k RAM and 96Kb VRAM
CPU
Neo-Geo - 12Mhz 16bit CPU + 4Mhz z80 co-pro (8 bit?)
GBA - 16Mhz 32bit CPU
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As you can see the Neo-Geo trounces the GBA in most aspects and there's probably not much in it with the CPU speed difference but remember that the Neo-Geo got released
11 YEARS
before GBA!