Well, quite honestly then, and I mean this with total concern for your bird and no disrespect to you, but I have to ask you a question then.... What if I'm correct and Chicky is miserable and depressed, and feels horribly out of place and constricted because of that fight suit? Do you actually think it's fair to your bird to make him wear something that is totally unnatural for a bird to wear? Do you think this could be a very unhealthy situation for him to be in? Birds are the most free animals in the world, and you're forcing him to not only wear clothing whenever he's allowed to be free and during his only free times in his life (or else he's locked inside a cage), but you are also messing with his GI Tract and his ability to have bowel movements normally, as already mentioned by other people...Think about that for a minute...You say that "You have to respect the other people in your house" and you cannot ever let him out of his cage without a fight suit on him, which could very well be the cause of his apathetic personality, but where is your respect and concern for HIS WELL-BEING? Again, I'm not saying this to disrespect you, but what you describe is a depressed, apathetic Green With no lust for life at all, and you're not even willing to even TRY to see if the flight suit is causing him issues, both psychological/behavioral and possibly physical/medical? That isn't fair to your bird at all; maybe it's not his issue, but again I would bet everything I own that it is and that if you gave him a week out of his cage with no flight suit at all even in his sight, you'd have a completely different bird at the end of that week...
***And just so you know where I'm coming from and why I think that the flight suit is causing him to be depressed and subdued, I'm basing this on over 8 years of being the Medical Liaison at a large, private Avian/Reptile Rescue, and I have seen many tame, pet parrots who were surrendered to us and who were suffering from an array of different physical and psychological issues just completely open-up and become different birds once we removed flight-suits, sweaters, sweatshirts/hoodies, harnesses, diaper-harnesses, fabric neck-collars, and many other forms of clothing/diapers/harnesses that their prior owners made them wear either whenever they were out of their cages or 24/7...I've actually seen pluckers who were put into sweaters or flight-suits to prevent them from plucking stop plucking completely once the suits or sweaters were removed. I've seen birds who were put onto antidepressants such as Prozac or Paxil, or sedatives like Haldol, due to apathy/depression/lack of energy etc. turn into totally different, happy, active, vocal birds as soon as we removed their flight-suits, sweaters, hoodies, harnesses, etc., and who I tapered off the medications after removing the clothing they were forced to wear, and they went on to be some of the happiest, healthiest, most vocal and energetic birds you've ever seen, instead of the quiet, morose, apathetic cage furniture that they were turned into...So as soon as I read your initial post and saw that he always has to be in a flight suit when he's not locked inside a cage, I immediately knew what is most likely going on...And keep in-mind that I have no stake in your situation, I don't know you and don't have any reason to even say anything about this at all, and I wouldn't if I had nothing to offer, and years and years of experience and education to back-up what I'm telling you...
Chocky is your bird and you're going to do what you're going to do, but I gotta say that if you at the very least don't take that flight suit off of him for at least a week and let him out of his cage, and actually allow him to be a bird and see if at the end of the week or two, after he has been let out of his cage every day without the flight suit, if his personality, attitude, energy level, vocality, etc. changes for the better, well, then honestly you're not respecting your bird...What if you did actually try letting him out of his cage every day for a week or two without the flight suit at all and Chocky did in fact turn into a totally different, happy, energetic, vocal bird??? Then what would you do, knowing for certain that the flight suit has been causing him depression for all this time? That's what you have to ask yourself because you're the one who is responsible for the health and well-being of your bird... That's what you sign up for when you bring any pet into your life.
I've had this exact discussion with numerous people/couples/families about everything from flight-suits to sweaters to medications to simply taking their bird to an Avian Vet once a year for a complete wellness-exam... sometimes they listen, sometimes they don't, but I have to say it because then I've done what I'm able to do to try to help their birds, reptiles, etc. I just think you'd not be really trying to make sure that Chocky is a happy, healthy bird if you didn't find out if that flight suit is causing him/has been causing him psychological and/or physical health issues...