Do not worry about what aspect of it? Where's the source for the full context?
I guess OP is referring to Christine Lagarde who said that banks shouldn't be worried about Bitcoin and Blockchain.
Found only this article from today:
https://www.cryptocoinsnews.com/imf-director-tells-banks-do-not-worry-about-bitcoin-blockchain/Lagarde's quote:
Many of you have heard about not only bitcoins but blockchains and that unbelievable technology that underlies the Bitcoins of this world at the moment, and how incredibly convenient it will be to actually generate trust and identify players and whatever pseudo they decide to use.
And many of you in the industry are actually worried that those technologies are going to massively disrupt the current industry.
If those new technologies and as long as those new technologies are going to abuse, take advantage of, the yield for anonymity, I think the banking industry has quite a few good days ahead of it as long as it takes ownership of those issues of capital and culture in order to actually restore the trust without which you see no trade no transaction no business can take place.
Damn yes these guys should be worried to get disrupted the next coming years.
As Andreas Antonopoulos said: "Bitcoin is punk rock.Deal with it!"