It can work for any corals depending on the exact light. There is not just 'T5' lighting, there are multiple types. There are normal output T5, but in a reef you want high output T5 (HOT5). In addition the reflector can make a massive difference. A single reflector is not what you want, you want one that has individual curved reflectors, meaning the reflector bends around each bulb which multiplies the amount of light that actually makes it into the tank by up to 3x.
Then there is the number of bulbs. With only two bulbs you wouldn't have many options, but six or eight high output T5 bulbs with individual curved reflectors would allows you to have anything you want.
The best looking and most productive (coral growth) tanks I have ever seen was HOT5 and it had SPS
growing like weeds and clams at almost every depth.