Christopher Green writes
Giant sequoia is hardy to somewhere below -20F, but its native climate
is much drier than New York is. With California native plants, wet
climate predisposes to all manner of diseases. Though it can live
thousands of years where it is native, I doubt a sequoia grove would
make the sort of perpetual memorial the WTC site deserves.

Stewart Robert Hinsley schreef
It grows quite happily in the British Isles, including sites which I
suspect are wetter than New York. Mitchell (Field Guide to the Trees of
Britain and Northern Europe) says it is frequent, but not thriving, in
towns, so perhaps there's something about the urban environment
(pollution?) that it doesn't care for.
--
Stewart Robert Hinsley

+ + +
It grows quite happily in the Netherlands too (on the other hand Sequoia is
not hardy enough). I think we get less rain than New York (we are getting
something in the range of 75-90cm/year and I seem to recall New York gets
more?).

Don't know about cities: it seems to be typically a park & Arboretum sort of
tree. Cities are full of Metasequoia and, especially, Platanus.

A more practical argument against planting in New York is that the City is
known for its furious pace while Sequoiadendron needs plenty of time to
reach an imposing size?
PvR