The other way around bud, a fnf missile does not guarantee hitting the weakest spot of a tank, if it does not then damage is minimal depending on impact sight of the tank armor. There is plenty of footage and news about this matter, drones can be guided to hit the weakest spot of a tank by remot controlled operator who has plenty of time to guide it, not to mention the fact that 20 drones cost less than a fnf complex and missile such as spike. At least 95% of tank losses are due to these drones, mines and artillery placing accurate rounds at the weakest spots. There is also a high probability that the crews operating spike, cornet anti-tank guided missile teams would be descovered by small drones with thermal devices. This is not to say that if a tank is within sight of such a system that it wont destroy it but operating such teams in close proximity to combat line is very risky business.Unless, jaming devices and some other counter to fiber optic drones, x-shaped drones (lancet etc.) are found they will remain way more effective than atgms of any kind.