Yes but security is done at each individual gate which makes a massive difference. And the staff is nice and polite. I don't remember ever queing for anything at Changi and I've used it so much. It's about the only airport I don't hate these days.
Security at the individual gate is also done at Kuala Lumpur, Doha, and some others. I prefer the usual arrangement of a centralised security check. This stack exchange answer does a good job listing some of the advantages and disadvantages of security at the gate:
Security isn't done at the individual gate in Terminal 4 (newest terminal). And actually security screening at the gate is a pain in the ass. Once you're screened you're stuck in a room with no bathrooms (you need to leave and get rescreened). And if your flight changes gates (happened to me), you have to get rescreened all over again.
It is helpful in the sense that bottlenecks don't happen earlier on, but I'm not sure it's that great of an approach.
It does have a massive mall attached to the public area though (Jewel).