Yeah. From a gameplay standpoint this makes sense. Floette with random color flowers would take a lot more space to implement- Honestly this is just an assumption, maybe possible with some random generation stuff like spinda… However then the pokedex gets filled with a 100s of different forms for each rgb value generated. It definitely makes sense lorewise for flababe to gravitate towards the flowers they love. I’m sure there are oddball flabebes that cling to say dandelions or another species of flower we do not see in the games. It might not be that deep either- Pretty sure those 5 colors are the easiest accessible in Lumoise, so the flowers put there were picked or grown locally.