I imagine part of the credit also belongs to Alec Baldwin. We meet a boyfriend of Phoebe's, Parker (Baldwin). Not only is this large and energetic man positive and enthusiastic about everything, he is complimentary about everything. Evidently, one of the show's writers had a boyfriend at one point with similar tendencies.
I think it is normally possible to choose one's emotions, at least up to a point. If you are seriously hurt or a loved one is, you are going to react. But much of the time, you can use your mind and your memory to see upsides to life. That is good but like many things, it can be overdone.
When I visit your house, I may be impressed with the excellent Norwegian recliners you have. The painting by your daughter is very nice and the photo of your whole family stands out. But when I go on to rave about the excellence of each house plant, maybe even waxing poetic about separate leaves on that one plant, it may get to be too much. I may get to be too much. I am not ignorant nor indifferent. I can see that the fabric on the lampshade is beautiful and I wouldn't mind if I had a lamp like that. But too much expression of admiration, appreciation, of deep impressions and maybe gratitude that I have gotten a chance to see your lovely, lovely things will probably get me stricken from your list of who to invite over.
It is even more likely that I will lose ranks on your friendship roll if I repeat that sort of behavior if you give me a second chance. Some definite positives, some authentic appreciation - sure. That is good and helps others as well as the offerer. But then, put a sock in it.