What makes it so retroarch will only work on 10.5 ppc systems?

[longboarder]

So I recognized that retroarch doesn't run on 10.5, and even if I run an earlier version such as 1.7.4 even if it says its compatible with ppc it wont run. Is there compatibility problems with retroarch? Can it be recompiled to work with a, say, 10.4 g3 or is there just libraries that 10.4 has that retroarch doesnt.

 

[longboarder]

Here, hopefully this helps:
Date/Time: 2020-06-13 15:45:34.462 -0400
OS Version: 10.4.11 (Build 8S165)
Report Version: 4

Command: RetroArch
Path: /Users/Thomas/Desktop/RetroArch.app/Contents/MacOS/RetroArch
Parent: WindowServer [59]

Version: 1.7.5 (1.7.5)

PID: 3696
Thread: Unknown

Link (dyld) error:

Symbol not found: _objc_setProperty
Referenced from: /Users/Thomas/Desktop/RetroArch.app/Contents/MacOS/RetroArch
Expected in: /usr/lib/libobjc.A.dylib

Model: PowerMac2,2, BootROM 4.1.9f1, 1 processors, PowerPC 750 (83.0), 400 MHz, 1 GB
Graphics: ATY,Rage128Pro, ATY,Rage128Pro, AGP, 8 MB
Memory Module: DIMM0/J13, 512 MB, SDRAM, PC133-333
Memory Module: DIMM1/J14, 512 MB, SDRAM, PC133-333
Network Service: Built-in Ethernet, Ethernet, en0
Parallel ATA Device: SAMSUNG HD103SI, 931.51 GB
USB Device: Hub in Apple Pro Keyboard, Mitsumi Electric, Up to 12 Mb/sec, 500 mA
USB Device: iPod, Apple Inc., Up to 12 Mb/sec, 100 mA
USB Device: Apple Optical USB Mouse, Fujitsu Takamisawa Component, Up to 1.5 Mb/sec, 100 mA
USB Device: Apple Pro Keyboard, Mitsumi Electric, Up to 12 Mb/sec, 250 mA