Bitcoin is worth something exactly because of people like Lagarde. It is our insurance against them.
For absolutist statements like her's, the only reason they are doing that is to promote their own digital euro in the form of a CBDC, which is good timing when a crash in the crypto markets happen.
How?
Even only this is enough, but there are many more ways this insurance works.
99% of this junk operates within centralized exchanges who can be forced to close it down and have a disproportionate level of influence on the currency itself.
It can be, and may do so under extremely small volumes, but the vast majority of people interact with this in a centralized fashion.