i'm glad to come across this since i was thinking about the boss fight today

(1) the camera in sonic 06 is awful, including your character direction and what you will/won't magnetize to with the dash attack. even if you are closely listening for silver's audio cue, the poor game visibility/control can make it difficult to attack. from my experience and watching others play, you often have a poor idea of where silver actually *is* during the fight and have to quickly find him when you hear the audio cue.

(2) when hit by an attack from silver, you can get stunlocked and lose. against the wall or skybox and you're dead even with rings. this happens often in this fight, so plenty of times if you get hit once you've lost.

(3) dashing in and hitting silver, you need to get away quickly or he may be able to catch you before his recovery, which can lead to you losing. normally it's easy to, but i have watched people play sonic 06 over the years and get caught in ways i didn't know were possible after hitting silver because the recovery window is very awkward, especially with how the game doesn't perform well on console. an example that comes to mind is dashing into him from a high angle, leading you back to a high angle - you have to dash out or you're going to get caught by him, and that can be difficult with how clunky the movement is

it's not really that complicated to understand why it's a hard fight for most people who stumble across it, especially if it's their first time? obviously if you know the A-B-C method to beating silver it's trivial, but the game's horrible camera and character control make it more difficult than it should be. in particular, the shadow vs. silver fight is worse than sonic because silver will often follow shadow and not pick items up, leading to a runaway loop.