Have you seen the captured kits? Some soldiers have cheap walkie-talkies (literally commercial off the shelf cheap Chinese brands), but many others have nothing.

If i recall correctly, their aircraft are supposed to be fitted with some high tech super encrypted communications system, but it doesn't work, which is why they use phones (with buttons).

It's not a matter of "the tech is too complex", it's more of a "the people supposed to implement/acquire/rollout this relatively basic tech pocketed the money instead".