They have a variety of attributes to use.
What does stealth bring to the table? I guess the question is for the defence of air crews and very expensive platforms as lesser states acquire more and more sophisticated air defences. They're not going to stand still. The Irans of the world aren't standing still to see what will happen to them militarily if something goes wrong. Russia and China are certainly moving to try to deal with and develop more sophisticated air defence systems, which will enable them to defeat American systems and not give up air superiority so quickly.
Stealth provides a basic technology or hedge against the unknown future. It's a mature technology now, at least for the United States and for the F-35. I would turn the question back to you. Why wouldn't we want the next generation of fighters, which is going to last 30, 40 years, to have the best technology we can put on them right now, notwithstanding the question of what other fighters are out there?