Absolutely. Since it doesn't reproduce readily, it was considered safe to grow in new habitats (which can be risky, for example all the noxious introduced weeds and animals such as star thistle and starlings), and it is successfully grown in western and southern europe and in new zealand and australia. It has been bred to create several ornamental types.
I have experience with it... after the 1987 fires that burned much of northern california, i was a reforestation specialist on the Klamath NF, and finding enough tree seedlings to plant that were ecologically matched to the sites was impossible, so the the state foresters helped out by making some their nursery stock available to us. On my district i received 50,000 giant sequoia bareroot 1 year old seedlings so my challenge was to find the best match of soil types, moisture, and weather band. The trees were planted in a mixture with native seedlings in a couple prior douglas-fir plantations that had burned very hot. Nearly every one grew. They are now about 40 feet tall, while the native firs and pines are about a third of their height. They are kind of like a bunch of Shaquille O'Neals amongst a kindergarten class.
Often, moving species to other areas can have unintended consequences, but giant sequoia doesn't really have many pests that are obligate to it (part of the reason they live so long) and the mycorrhizal associations that help it gather certain nutrients are shared with most forest trees wherever there is a mediterranean climate.
So yeah, depending where you live, you could probably successfully grow it as an ornamental.. its limiting factor is cold... it doesn't handle lots of subzero cold well, and gets windburned in the face of subzero wind conditions, which kind of makes them not look like a great specimen tree in your yard if half of it has red needles.
