There is a key, vital difference between proverbially jumping in front, which does not deprive agency, and forestalling even the possibility of choice, which does--and is railroading. You can still attempt to do things, you just might fail. As is the case with literally anything people attempt that then gets met with a dice roll, ever.
Again, I challenge you to tell me why "missed the attack roll" is not railroading, given your definitions. Unless, of course, you wish to bite the bullet and admit that you do think missing attack rolls is railroading
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Just because you don't succeed, doesn't mean you didn't try. Like, again, that's literally why I gave the example I gave. People can TRY things all they like. They aren't guaranteed to succeed, and players having agency is NOT the same as "every single thing you ever attempt will always happen exactly as you envision it."