I've never understood the need to bash OS4 by people who don't use it.... but all it does is drive a thicker wedge between groups of Amiga users.
AmigaOS 4's existence does not suddenly mean that 68K Amigas stop working - it's quite possible to completely ignore it if you don't like it.
Not entirely sure where the idea that "AmigaOS 4 is so bad" came from anyway... must have been using a different OS4 to me, as mine is pretty awesome really.