Is Tradition Rigid?
In so far as rigid means "not able to be changed or adapted" the modernists employ a rigid adherence to their heresy, idolatry, blasphemy, and their Babylonian agenda.
So the term is just being used as a pych-opp.
Let's apply the last 2 paragraphs of the Rule of St. Benedict to Catholic Tradition:
"What else are they but tools of virtue for right-living and obedient monks? But for us who are lazy and ill-living and negligent, they are a source of shame and confusion.
Whoever you are, therefore, who are hastening to the heavenly homeland, fulfill with the help of Christ this minimum Rule which we have written for beginners; and then at length under God's protection you will attain to the loftier heights of doctrine and virtue which we have mentioned above."
Catholic traditions and customs are the tools of virtue for right-living, for those who reject the tools, the tools are a source of shame and confusion, for it's with the use of the tools that we attain to the loftier heights of doctrine and virtue. We can now see that those who reject the tools, sooner or later reject the doctrine and virtue.