Presumably, the book goes into depth about the folks who actually did the work:

- Susan Kare and Keith Ohlfs who did the UI design

- Caroline Rose (Author of _Inside Macintosh_) who wrote the documentation

- Avie Tevanian (the most heavily recruited CS student at that time w/ job offers from Apple, AT&T, IBM, and Microsoft) who wrote the Mach Micro kernel

- Brad J. Cox (author of https://www.goodreads.com/en/book/show/1945013.Object_Orient...) who created Objective-C

- Jean-Marie Hullot who created Interface Builder and which made Steve Jobs' "5 Minute Word Processor Demo" possible

- Mike Paquette who wrote Display PostScript (and then, repeated that by writing Quartz, née Display PDF after the Apple bought NeXT) --- his posts to Usenet:comp.sys.next.* are a hoot and well worth looking up

- John Anderson and Bill Tschumy who wrote WriteNow, first for the Mac, then porting the ~100,000 lines of assembly to NeXtstep

(for a couple of years, MacExpos were SJ showing off things previously shown at NeXTexpos to thunderous applause)

That NeXTstep included a number of major advances/breakthroughs (7) was noted in the advertising at the time, suggesting that the reader of the ad could then create the balance for a total of 10 --- some of my favourite apps:

- Lotus Improv --- Lotus didn't dare kill of Lotus 1-2-3, so they wrote a new program, which had SJ sending them bouquets of flowers --- a recurring theme in _NeXTWorld Magazine_ was a list of applications which were wanted, and when developed were described as "in the bag" --- really wish I could justify Quantrix at work, or that someone would update the code for Flexisheet so that it would compile....

- Altsys Virtuoso --- v1 was created by the team behind Freehand v1--3, and v2 of AV was ported to Mac OS and Windows as Macromedia FreeHand 4 (a .vrt file could be opened by FH4 by changing the file extension of the .vrt file in the document bundle to .fh4)

- the map builder for a little game called _Doom_

- a full-fledged desktop publishing app by Glenn Reid (author of PostScript Language Design (the Green Book) and https://www.goodreads.com/book/show/8260463-thinking-in-post...) Pages.app by Pages, Inc.

Other ports were notable, but more prosaic w/ WordPerfect being notable for taking full advantage of Display PostScript and Services and being done in just 6 weeks time (easily done since they started w/ a working Unix version).

It is notable that for a long while, WebObjects was basically keeping the company alive, with major vendors including the USPS and Dell (that latter was a major embarrassment to MS, and their efforts to change Dell over did _not go well and garnered some notable press).

Sad my Cube no longer boots, it w/ a connected Wacom ArtZ, paired w/ an NCR-3125 (since donated to the Smithsonian) running Go Corp. PenPoint (and later an Apple Newton MessagePad 110) represent the high-water mark of my GUI experience and got me through college --- these days I use a Samsung Galaxy Book 3 Pro 360, Kindle Scribe Colorsoft, Samsung Galaxy Note 10+, and a MacBook w/ Wacom One, but I still run Freehand/MX....

- Steve Naroff who basically hacked together Objective-C++ in a few weekends. His interview with the Computer History Museum is worth a watch.

Weird to state all these details, leading with 'presumably'