IIRC, the M113 was intended as a stepping stone to more advanced IFV’s and even tanks. That would mean that it’s chief virtues in this training mission is simplicity & availability.
A little surprised that they aren’t using BMP’s, but we are speaking about a US training mission here.
The IA has BMP1s and is also buying BTR4s.
They are getting these M113s for the price of refurb and transport.