It's more about what you believe suits you and your bird. There are people who will Quote safety, the ease of training, behaviour modification or cruelty. I have two Alexandrine Parrot who are fully flighted and have had no problems in regards to safety, training or behaviours. But that just me and I spend at least 2 to 3 hours each day minimum interacting with Delfin and Mulawa.
Delfin who I had the longest of the two is very attached to the family but more to me. Delfin has been out of the cage and both the back and screen doors have been wide open, yet Delfin just sat on my shoulder. I have put the bird stand next to the glass sliding door so he can look out through the glass. He is just not that interested in the world outside.
Mulawa is different, has she is the newest member to the family and is still finding her place in the family. With training and interactions she is becoming more confident and out going. Delfin and her are now pretty attached to each other and the family.
I have shown Delfin and Mulawa the windows and they understand the windows can't be flown through. Delfin and Mulawa are never left un-supervised as there are a lot of dangers inside the home. The biggest danger in our home is the 240v power leads and while they are hidden away, I'm not a fan of putting power leads under cover, especially under rugs.
I believe that you don't need to clipped a bird's wings to achieve good results from training. instead you need to spend time with your bird, lots and lots of time with your bird. This doesn't mean you have to spend all that time training your bird tricks. Just having your bird sit on you while you are washing up or folding up clothes or even while you're on the computer is a good interaction.
I never really had any behavioural problems with Delfin and Mulawa to where I would have considered clipping their wings. I have read of the logic behind wing clipping for behavioural problems and also what can happen when the bird is allowed to grow back it's flight feathers.
Apparently the logic is to remove the birds ability to fly and make it more dependent on you, therefore it's easier to train and will calm down behaviour wise. The bird is intelligent enough to know that it can't fly around and do what it wants, it now has to behave. Note the reason the bird was misbehaving is that it probably didn't get enough interaction / training time or it just doesn't like you.
When the flight feathers grow back in, what happens next depends on wether the bird has grown to like you or not. If not, then there will be hell to pay. This is because the bird is now fully flighted and can fly away from you easily.
I'm not sure if it's cruel has it not a permanent outcome. There are some species of bird that would probably cope better then others. But I believe that wing clipping affects each individual bird differently mentality and physically regardless of the species.
I understand there was a surgical procedure called wing cropping. I'm not sure if that is the correct term. But this is cruel, has part of the wing was surgically removed. This procedure is out dated and is in the scrap heap where it belongs.
The choice is up to you, do has much research on this topic as you can and then make up a list of positives and negatives for your situation and so you can make an informative decision before committing to wing clipping.
but remember clipped birds can still fly, just not that well. once done, it can't be reversed until the bird moults.