I would say that it is the most complete typesetting system out
there that I know about¹
It is not the optimal system that could possibly be created.
for many reasons.
However as people design new typesetting systems or various kinds,
and they make it the priority for it to be simple.
Then usually over time users become restless because the
markup langauge misses a typesetting feature they would like.
And we wee a plethora of markup forks of all sorts that include
one set of typesetting additional features that the authors
deemed nessescary.
The more you devlelop an alternative typesetting system, eventually
you will need features that are all already included in TeX.
and they are included because they were needed in an advanced
typesetting system that would give people the tool needed to
highly polished outputs.
But TeX is not a system for the masses, nor was it ever meant to be.
¹(There may be systems just as good used by print media)
It is not the optimal system that could possibly be created. for many reasons.
However as people design new typesetting systems or various kinds, and they make it the priority for it to be simple. Then usually over time users become restless because the markup langauge misses a typesetting feature they would like.
And we wee a plethora of markup forks of all sorts that include one set of typesetting additional features that the authors deemed nessescary.
The more you devlelop an alternative typesetting system, eventually you will need features that are all already included in TeX. and they are included because they were needed in an advanced typesetting system that would give people the tool needed to highly polished outputs.
But TeX is not a system for the masses, nor was it ever meant to be.
¹(There may be systems just as good used by print media)