My 2 cents...
If you only have one CX-5 you won't notice a difference because you don't have another one to compare it to.
I guess it's safe to say the 20s are quieter than the other years, but you need to decide if paying new car price is worth it for a slight difference in noise level. I have a 19 CX-5 and I think it is plenty quiet, don't even think about road noise while driving. Sure, an even quieter cabin would be nice but the CX-5 is already excellent in the NVH department. Humans have an incredible ability to tune out ambient noise anyway. Point is, I think you'll be satisfied regardless of which year you end up with.
If you only have one CX-5 you won't notice a difference because you don't have another one to compare it to.
I guess it's safe to say the 20s are quieter than the other years, but you need to decide if paying new car price is worth it for a slight difference in noise level. I have a 19 CX-5 and I think it is plenty quiet, don't even think about road noise while driving. Sure, an even quieter cabin would be nice but the CX-5 is already excellent in the NVH department. Humans have an incredible ability to tune out ambient noise anyway. Point is, I think you'll be satisfied regardless of which year you end up with.