When I started in this hobby some 13+ years ago, SPS where the Holy Grail in reef keeping. You rarely saw SPS for sale in a LFS and not a lot of people kept them, that is to say kept a SPS dominated tank. Back then PC lights where the in thing!
This hobby has come a long way in husbandry and equipment. Now hobbyist can keep more of a variety which includes shapes, color and sizes of SPS. There is also more of a variety available on the market.
I would also agree with a number of the comments above. It is progression of the hobbyist to try keep more challenging corals etc.
I jumped on the SPS band wagon years ago because it was the Holy Grail. Now, well I've been there and down that. But, I'm now trending towards certain shapes and colors to fill the tank out. Sort of what FutureInterest is saying. As far as colors, some the LPS that are on the market these days certainly blow the colors of SPS out of the water, but you'll pay for those. But the dont give you the shapes and dimensions of an SPS.
Also, part of the fun of the hobby is to buy a 1" stick, plant it and watch it grow. See my avatar that started out as a 1" stick.