I understand what you says, I partly share your idea, but indeed a modern army must be on top and give the best to these soldiers. What often gives the advantage to the armies is not that their clothing or more glass or that they have an M-4 modernized against an AKM, but rather the technological dominance, the support that the army sees again during a battle, for example in Afghanistan when NATO armies fell in ambush, they immediately asks for air reinforcement to have the advantage, otherwise they will be in troubles, despite their equipment.
Afterwards, yes, it's clear that when your soldier is better equipped, he has a better mind, when you give him more suitable shoes with better comfort, he will feel it on a daily basis, when you give him a lighter bulletproof vest , he'll feel it too, it'll be a plus for him, if you spend your days complaining about your foot pain and that your vest is getting in your way - you'll soon be in a bad mood for being there.
Also to have radios and individual NVGs, they should launch the mass production of this equipment which has become standard equipment in any soldier of the 21st century. I don't bury the Kalashnikov personally, it's an effective weapon, robust, reliable and above all easy to repair in the field with the first piece of scrap lying around on the ground so changing it would be a big mistake.