Could become a nasty strat if you made them cheaper and survive ATG shot. Couldn't you then just spam 3 of them into the front line full of dudes, jump out and rape the support?
Sorry, don't mean to theory craft, I just seen a lot of abuse in the past years....lol
If it could survive a single ATG shot, then you'd be left with 30-50 hp (Depending on brand of ATG) if it were buffed up to 180 HP... Where no more than 8-9 hits from any infantry rifle will destroy the vehicle, as the vehicle armour can be damaged by literally anything (Jeep armour).
It's a change intended to make them more appealing so you don't risk losing your inf to a sudden shot out of nowhere, which is why they aren't used now. That and 15 FU is still a bit much. It could be dropped down to 5 FU, or even just cost MP considering it has literally zero armour.
If you try and rush 3 of them at a line which has an ATG and an MG, chances are you'll lose all 3 of them, 1 at a minimum and 2 highly probably. Not to mention if every one had a squad in that's 15 pop for the inf at least and 6 pop for the 3 transport trucks. 21 Pop's worth right there, which'd get minced by pretty much any kind of ATG + small arms.