See i disagree, you cant compare Garen's Silence with Talon's silence, those are two totally different abilities with totally different mechanics. Garen can not 100-0 someone like Talon can, Talons is also an instant Gap Closer meaning you can not escape once in range whereas you can just run from Garen or CC him or flash before it hits you. It would be better to compare LeBlanc and Talon, but they both got their silences removed for having the exact same problems, the same with Kassadins Silence... see where im going?
They are already doing what you are suggesting they shouldnt do, Assassins with silences are too overpowered and offer no counterplay. Burst mages like Annie and Veigar having instant point and click stuns offer no counterplay. You are so caught up on the fact Annie and Veigar are different champions that you cant see what makes them so similar. They both just moved their mouse to an area and click their stun, you dont know when or where it will happen, you dont know whether you are in the danger zone or not, all you know is that you are about to get stunned the moment they get near you. Just like with Kassadin, Talon, and LeBlanc you knew you were going to get silenced the moment you got in range regardless of what you do (other then going untargetable or using a spell shield of course, but thats counterplay to literally everything so it doesnt count).
Im not saying Annie needs a delay, i was just saying it as an example, but they need to balance everyone fairly. This is why Lee Sin is so hated, he is not being balanced according to the same rules as everyone else (honestly he just needs some damage tweaks in my opinion but thats another discussion id be glad to have with you if you are open).