The first Smalltalk JIT was written for the 68020, so the NeXT hardware would have been suitable. EDIT: OTOH, The Tektronix AI Workstations had already been on

The first Smalltalk JIT was written for the 68020, so the NeXT hardware would have been suitable. EDIT: OTOH, The Tektronix AI Workstations had already been on sale for a while by that point and had not been all that successful. They ran Smalltalk on top of a UNIX-like OS, not directly on the HW.