string_view is a thin wrapper around C strings, so it's more efficient
for constant strings than C++ strings.
The unordered_set<> also adds extra runtime overhead. For small arrays,
a simple linear search works. For larger arrays, std::binary_search()
works better than linear but without the unordered_set<> overhead.
ShouldBeDualLayer(): Removed a duplicate "SK8X52" entry.