Most Amiga users - at least the home computing/gaming enthusiasts - never saw a big-box Amiga back in the day. To most users, 'The Amiga' was the A500, which released in '87 and reached peak popularity in the very late 80s/early 90s.
And to most Amiga gamers, Doom was where it became clear the PC had overtaken. Amiga game developers also got obsessed with trying to build a Doom clone for the Amiga, repeatedly showing how futile that effort was* , and much talent was wasted in that pursuit rather than making more good 2D games.
But by the time Doom arrived, the SNES had already been out for a couple of years, too, and despite a weak CPU it absolutely destroyed the Amiga in terms of 2D graphics performance (multi-layer parallax, loads of sprites, loads of colours, and 'Mode 7' effects)
(*ok, maybe not entirely futile if you've seen Dread/Grind which are super-impressive, but it took until the 2020s to pull it off, with an engine that seems about halfway between Wolf3D and Doom in terms of capabilities)
And to most Amiga gamers, Doom was where it became clear the PC had overtaken. Amiga game developers also got obsessed with trying to build a Doom clone for the Amiga, repeatedly showing how futile that effort was* , and much talent was wasted in that pursuit rather than making more good 2D games.
But by the time Doom arrived, the SNES had already been out for a couple of years, too, and despite a weak CPU it absolutely destroyed the Amiga in terms of 2D graphics performance (multi-layer parallax, loads of sprites, loads of colours, and 'Mode 7' effects)
(*ok, maybe not entirely futile if you've seen Dread/Grind which are super-impressive, but it took until the 2020s to pull it off, with an engine that seems about halfway between Wolf3D and Doom in terms of capabilities)