Actions and Consequences
A friend of mine once defined the problem of fundamentalism as being when a person lets one factor dictate everything, without recognizing that there are often a multitude of factors to consider. Life is rarely simple and even if there are strong grounds for pursuing a particular course of action, there are usually other factors that must be considered.
Rav Shlomo Zalman Auerbach ztz"l did not seem to make that mistake, at least in the area of kashrus. Based on questions that I asked him, and discussions that I had with others who had more extensive contact with him, my impression is that he weighed up the consequences. While he no doubt took kashrus very seriously, he also weighed up meticulousness in kashrus against other mitzvos and values. Thus, in certain circumstances, he recommended not being particular about certain kashrut stringencies where it would risk compromising shalom bayis.
One example of people doing the opposite is with the practice in some Orthodox circles to never allow a woman's face to appear in print. Now, I can understand and sympathize with the motivation behind this, even if I don't feel that way myself. But the people engaging in this practice only think about the reasons for doing it. They never seem to take into account the possibility that, regardless of whatever good reasons they might have, there can be negative consequences which might outweigh it.
At a broader level, this seems to have happened with halacha in general. Over the last few decades, there was been a tremendous increase in stringency. This was often done in order to strengthen halachic observance. However, people don't seem to have considered how it can actually have the opposite result. In an age when people are more knowledgeable and independent-minded, they can recognize when halachah has been chumrafied for unsound reasons. This undermines their confidence in the halachic system as a whole.
Tafasta meruba, lo tafasta.