I wrote up something much longer than this, then deleted it because I think the point got lost in the details.
As with the Macintosh 6200 family, I think that these systems often get mis-judged. We often end up comparing them to systems that cost a lot more and had different form factors and ultimately different market segments.
By 1993, you could get a Color Classic for $1,200 or so, often with a copy of ClarisWorks. That was several hundred dollars short of any other Mac. A 605 was $980 but you'd need a $320 monitor and an $80 keyboard, absolute minimum, to boot it to a usable state, and the $320 monitor was inferior to the Color Classic's display. (Well, it's a bit of a wash, it was a shadow mask 640x480 display.) (This is all Apple's own US pricing from their mail order catalog.)
I've got the CC's monochromatic sibling, the Classic II, and, sure, it's not as fast as my 840, but, to be honest the 840av isn't
fast either. I use it because I like the form factor, and I think that it's important to consider what regular people might have had access to -- because, well, an 840av wasn't really a reasonable purchase for a home user at the time. Once an application is launched, it basically runs fine. To be honest, even AppleWorks 5 and Claris Organizer 2 from 1996 and 1999 respectively run fine on the CII, even when it's connected to an AppleShare server over LocalTalk.
Adjusted for inflation, the IIfx was probably the most expensive Mac ever released. Shipping it with but 32K of L2 and no attempt to develop/implement L3 Cache in a $10,000 workstation class machine was inexcusable IMO.
Level 3 caches didn't exist until 1995 in DEC Alpha 21164 machines, probably only the big ones that would sell for minimum $30,000 or so. It didn't re-appear again basically at all anywhere else at all until 2001-2002 when it appeared in some POWER4s and in the PowerPC G4, where it was used to compensate for the fact that the Mac G4 had a system bus and memory half to a sixth as fast as what you could get in a Pentium 4.
Apple used a
lot of go-fast tricks on its very highest end systems. I don't think it's inexcusable per se that they didn't happen to stumble upon this one, and, I think it's important to consider what pricing would have looked like on a Mac that did, especially in 1989.
The important thing to remember is that as part of its 1990s ethos of trying to be literally everything to everybody, they absolutely had to be selling "cheap" Macs. It's tough to say whether each choice they made was as an attempt to specifically sabotage low end machines, or as an active attempt to keep costs down.
Given that 1987-1997 Apple is such a favorite era, I would presume to use the generous possibility here and say that it was an attempt to keep the machines reasonably priced.
A lot of the intent of Apple's lowest price computers, and I think it would be fair to read this intent into almost anything Apple has sold at a low price, is to force the technology to exist at a price more people can afford. A $999 Classic in 1990 was favorable to the alternative of "not having a computer" -- a $1200 Color Classic in 1993 is favorable to the alternative of "not having a computer" -- so on and so-forth.
Apple stopped (for a while at least) differentiating between "pro" and "consumer" systems on the performance front in 1998 with the release of the iMac, and, that next couple years were a revelation in what could be done between the fact that costs for all tech had fallen so much over the course of a decade and with a simplified product lineup.(1) I question whether or not that would have been feasible prior to then. Even on the PC side of things, you had budget-oriented machines selling with years-old components and platforms that made compromises to achieve a cost objective. The PC-market equivalents to the Classic and LC families did all the exact same things, beat-for-beat.
(1) sidenote w/re that: they started differentiating in compute guts again almost the literal instant they had something
worth giving to pros, with the G4 and then the G5, but still.