Prices for raw coffee beans have seen inflation like any other. Add to that the cost of everything else that goes into the sourcing, roasting, packing of coffee beans, then to the cafe for grinding, preparing and making your coffee (sometimes with milk - dairy prices also up) so $6.50 or thereabouts is not crazy anymore in the current world standard. I was paying 5-6 euros when I visited some nice cafes in europe 3 years ago.
NZ enjoyed amazing good quality coffee for years at $4-4.50 but this is not sustainable anymore.
I reckon around $7 a cup will and should be the new standard if you want a decent cup of coffee from a proper cafe. More if you opt for alt milks like oat, coconut, almond etc.
A good alternative is to invest in a good quality coffee grinder $100-200, buy your own whole beans from your favorite roaster, and brew hot coffee yourself using something simple like a french press or a moka pot - both great if you like your coffee black. You can also get a milk steamer/ frothing wand if you need/want it white or add hot water and a dash of milk. This is much easier than the $1000's home espresso machines which are not the easiest things to use. Nespresso machines are also quick and easy but taste is..