At least color in the red and magenta range tends to intensify when bloomed under cooler temperature and very bright condition.
Roots in moss...I hear your concern.
Once you see how tightly the stuff is packed in, and often some roots are suffocated to death being stuck in there, each time you buy a phal potted in moss, it worries you.
I think it's best to repot it to at least "relax" the moss a little at the least.
I normally repot when florwers are all gone mainly because I don't want to take a chance on damaging any flowers.
Now, I can also get really lazy or forgetful and do not repot phals in moss for a long time. somtimes too long. I have never killed any!
The key is a very careful watering to minimize the root death.
I have about 10 phals in moss. Some were bought over a year ago ( I know, I'm terrible sometiems) and some are pretty recent purchase, about three months ago.
The ones I haven't repotted over such a long time is because they keep flowering. so I just left them alone. These are also in clay pots, so I think it at least "breathe" better. All the phals I buy from a farmer's market come this way, potted in moss in clay pots.
Now, other phals bought in mostly grocery markets come in this very thin clear plastic pot slid in decorative ceramic container.
These are the ones whose roots look quite bad.
All are pushing new leaves and roots at the moment and I am thinking of ordering some pots and potting mix online over the weekend before another year passes by again.
Now, I'm just sharing my experience and not recommned leaving phals in super tight moss.
just saying they still go on and live under "strict watering"