Tourists tend to avoid places where they might get killed by Muslims.
London is still safer than New Orleans, Detroit, Milwaukee or Oakland.
Sanctuary cities, especially those ran by Islamic mayors that dismiss Islamic violence as to be expected against Christians, should be avoided as a commonsense measure. No surprise that people would not go there.
Terror fears and the knowledge that most of London’s cops aren’t armed.
“Why, I’ll never go back to that zoo!” —Tennessee Tuxedo
Statistically the risk to any one visitor is vanishingly small. Remember that last week’s atrocity was the first multi-casualty terrorist attack anywhere in the UK since 2005 (during which period there were four in the USA).