It obviously matters more if it is your primary score, but I think it has impact otherwise too. And it actually might lead the boosted score to be more than that two points better. Like is I was playing an elf cleric and got that +2 to dex, I would be more inclined to put at least 12 to dex for a free 14, and might be more willing to choose a cleric subclass without heavy armour. And as I now have that +2 dex modifier, I might be interested in getting some dex skills. I would also then use dex based weapons (granted, in 5e clerics are sadly poor weapon users.)
In the end, there would be a good chance that we end up with a cleric that comes across as more agile than average; fitting for an elf.