> The parent comment literally admitted that they were removing specific complex topics.

you quoted and responded to

> although they are cutting geometry a bit, which doesn't make as much sense today as it did 100 years ago when far more people grew up to be farmers or ranchers

so which specific and complex topics are you referring to in the OP?

But also replacing it with other perhaps more pertinent advanced topics? Hard to have a fruitful discussion without a curricula to discuss