I've used nroff/troff/TeX with many of their various macro packages over about a 35 years span.  During that time, I've done many single-page documents as well as documents as long as 350 pages.  I also modified a version of nroff to create business forms for Laster printers.  This is still being used commercially.  This is one person's opinion:

1.  Perhaps owing to my limited intelligence, and in spite of the fact that I've used TeX successfully on many documents, I have never been able to fully understand TeX.  Apparently, it is too much for me.  Troff, on the other hand, has made full sense to me.  I was able to make it do what I wanted almost always.  I enjoy using troff more because I find it simpler, and therefore, more pleasant to use.

2.  Looking at the output, it is my opinion that TeX produces better-looking documents.  Perhaps this is just no more than one man's esthetic opinion.  I do not know what it is that I find better.  It's just the sense I get.  On the other hand, I find troff output to be sufficiently good in nearly all cases.

3.  troff is a good and reasonable tool.  TeX is too big and complex an environment in most cases.  Although it is true that all of the complexity of the TeX environment is successfully hidden in virtually all cases.  I find the huge and complex environment offputting.

Very unfortunately, I see troff disappearing.  I've worked with a number of teams over the last ten years.  In every case, I was the oldest engineer.  Also, in each case, I was the only engineer who had even heard of troff.  They understand the problems of binary formats such as Word and OpenOffice.  Their solutions are things like markdown, AsciiDoc, et al.  They are doing this development and making use of these tools without knowledge of troff.  The same is true to a greater or lesser degree with TeX, except that I've seen TeX used at universities.

I like that groff and TeX are rock solid and well supported.  In fact, I wrote a report generator for a modern web development framework using troff.  I use it to develop reports on a routine basis.  (kissweb.org)
Sadly, however, if word of their existence doesn't get out there, I see them both disappearing in not much longer than a generation.  This would be sad indeed.

Blake McBride

On Fri, Dec 31, 2021 at 9:16 PM Larry McVoy <lm@mcvoy.com> wrote:
On Sat, Jan 01, 2022 at 11:56:05AM +1100, Greg 'groggy' Lehey wrote:
> > The only negative reaction was table of contents complaints, LaTex is
> > 2 pass so it can do them, roff is one pass so you have to fiddle with
> > things.  A lot.
> I solved that issue in later documents with two passes in the Makefile
> targets, frobbing things like references and contents in between.

I was troff friends with W Richard Stevens, he shared with me a lot of
what he did in troff.  He did the two pass thing.  Nice guy and got as
much out of roff that anyone could, all of his books were troff.