The general goal of every Marxist movement is to undermine or sabotage any opposing culture using whatever means necessary so that it can be scrapped and replaced with a new progressive/collectivist system.  In particular, such activists have long targeted western civilization for demolition with the intention of bringing about a woke revolution.

This is why we often see the same people (or types of people) involved in seemingly separate causes.  It might be protests and riots in favor of BLM, it might be Antifa efforts to disrupt conservative and moderate speakers, it might be protests to control college campuses in the name of Gaza or it may even be anti-carbon protests to derail energy security in the name of "saving the planet" from a global warming threat that doesn't actually exist.

Most interesting is the habit of Just Stop Oil activists to target famous symbols of western history for defacement or destruction.  One might ask what does the Mona Lisa or the Magna Carta have to do with oil production or climate change, and the answer is absolutely nothing.  Protesters would claim that trying to destroy these antiquities is a way to get media attention for their cause, but the only attention they ever get is negative - These actions make people want to hate protesters rather than help them. 

The real message is one of aggression, not attention.  Marxist activists are saying that western culture, not oil, is their enemy. And, if they don't get what they want they will continue to try to smash our greatest works of art and historic documents as a means to tear the west down piece by piece.  When protesters declare the Magna Carta fair game it's not a random decision; they know exactly what they are doing.  In this situation, two gullible elderly women were obviously given a task they were not able to complete: