A problem with Visa cards does not necessarily mean that people will stop using it or resort to alternatives such as Bitcoin "It's a technical problem as long as the money is safe, trust is there."
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Events like this one, or the recent UK's TSB bank IT migration mega-failure, could shift (affected) public perception in favour of crypto and decentralisation. The problem is, although most have at least heard of Bitcoin, the average person is absolutely clueless about how Bitcoin works and what 'decentralisation' means. Shame, because this would be the great opportunity to get more people on-board.
So probably the only real, immediate effect (if any) is that the current bitcoin holders will appreciate it a little bit more.