Sir even with external load outs the RCS of F35 shall be fairly low, meanwhile Israel already has good relations with most countries through which they shall pass. The Syrian SAMs are quite credible yet IAF conducts regular air strikes with minimal losses there.
Sir Taliban are not a regular force further when they were acting as a regular force Taliban got defeated within few days. They have waged a irregular war, in which they have no central structure, they act in small groups with own strategy, off course terrain and local public support is also there in Pashtun areas.
Believe me Taliban are also armed with modern weapons though lighter and suitable for guerrilla attacks. Further the Afghan Govt structure is artificial mostly based on warlords meanwhile for face saving few highly educated Afghans who have no roots in their country are given key positions.
The Americans and allies are acting intelligently as on one side they have persuaded Taliban to keep some sort of military presence in Afghanistan as well as they are able to get major restoration projects and mining projects in the country, even civil security contractors are also there creating thousands of jobs for their own people along with financial benefits. The USA in most of cases remains in win win situation.