The TT was severely underpowered as a UNIX machine when it came out (and not that inexpensive) - a Sun 3/60 had comparable features already in 1986 (I had a TT which I sold since I couldn’t get my hands on Atari System V and then got a 3/60 which I still own). By 1992, the second generation of RISC machines by Sun, DEC and others was on the market which significantly outperformed the 68030.