This in particular.
It got flagged, as not an answer, it passed review and now is flagged again.
What should we do?
Definitely a comment, not an answer
Personally, I don't see how it answers the question "Do any airports have a steeper standard approach than London City?", since, as said in the comments, the mentioned airport is only mildly steeper than a usual approach.
I would vote to delete.
When I saw it earlier, I thought it was not an answer, but I'm having second thoughts. The poster thought of an airport that may have a steeper approach. As it turns out, that was wrong, and the airport has a shallower approach. As an outright, unsupported guess, it's a pretty poor quality answer, but it is a good-faith attempt to answer the question. The fact that it was wrong doesn't make it NAA, and we don't typically delete answers just for being wrong.
That said, remember the rule to "optimise for pearls, not sand". This attempt at an answer is definitely sand, not pearls, so let's not worry too much about it either way.