The funny thing about the heresy of Modernism is that it doesn't claim to restore the "true" ancient teaching like the old heresies all claimed. Instead it proclaims a "brave new world" where the apostolic teaching has "evolved" or been "updated" to meet "modern needs". It's remarkable when you think of the massive revolution in the West and in Catholicism in the 20th century that the Modernists may have brought on crisis and catastrophe, but they didn't prevail, and their influence is steadily on the wane in the Catholic Church even as the are triumphant in outside society.
The question i am addressing is whether or not the teaching of the Catholic Church has been updated to meet modern needs. According to what you say here, modernism is steadily on the wane in the RCC.
However, I don't think that is true. And the example, that I give is the example of the teaching of the RCC on what constitutes a valid marriage. Before Vatican II, annulments were given for only the most extremely serious of solid reasons. After Vatican II, in the USA, almost anyone can get a marriage annulment for very trivial reasons. For example, consider the book: Judging Invalidity ©2002, By Fr. Lawrence G. Wrenn. This book is "Designed as a practical companion to the author's previous volume, The Invalid Marriage, this resource for tribunals, students and pastoral ministers contains 15 fictional marriage cases. These reflect the basic grounds for marital nullity established in the 1983 Code of Canon Law."
Reasons for annulment listed in Judging Invalidity ©2002, By Fr. Lawrence G. Wrenn
Working out a couple of hours a day in the gym.
Being described as arrogant and selfish with an "I don't need anyone else" attitude.
Saving one's salary in a personal account.
Seeming to be obsessed with one's body (personal appearance).
Ignoring one's parents on one occasion when they came for a visit.
Seeing the world as his apple. (Psychiatric expert's term)
Never being satisfied with a gift given by one's spouse.
Feeling chronically disenfranchised in one's (spousal) relationship.
Not achieving the desired companionship and intimacy one wants in marriage.
Suffering abandonment issues over a father who died.
Protecting herself by putting a hard shell around herself.
Suffering from low self-esteem, self-absorption, and a need for attention.
Lacking emphathy and fearing intimacy.
Comparing oneself to others and always finding them happier.
About a month before the wedding he drove his mother to a family reunion, leaving her all alone to make preparations for the wedding.
The psychiatric expert described the respondent as porcupinish. He didn't want people near him; surprises he liked even less. It was noted in the proceedings, however, that he was in love with another woman.
The petitioner's mother always resented her. The mother was unreasonably strict and hypercritical.
Obviously, these are things that can come up in any marriage.
So it is clear that contrary to what was written by the poster quoted, modernism has entered the Catholic Church since, for example, the annulment process has been watered down to the extent that almost anyone in the USA can get a marriage annulment .