Coffee – discernible difference in taste between aeropress and chemex / pour-over

It could simply be that it's a gustatory illusion! See my answer to this related question for more explanation.

Edit:

Here is a summary of the relevant information (if you don't want to follow the links):

Human taste receptors don't simply react to how much actual salt there is in a food or drink; our perceived tastes are a fusion of both our gustatory and olfactory senses. In other words, the smell of a food or drink can affect how it tastes!

There are numerous studies that suggest foods with certain odors can be perceived as much saltier than they actually are. Coffee has a good amount of oil, there's even more fat if you add cream, and other studies suggest that high fat foods can also increase perceived saltiness.

To me, the best thing about the pour-over method is that you can experiment without wasting much.

A few more details about your equipment would help. How big is your "level scoop," what shape are your filters and are you using paper filters? I make mine with a simple plastic #2 cone filter holder and paper filters and don't have any issues with clogging with about 2 Tbsp of beans.

Are you using a proper grinder or one of the whirling blade style? The blade-type can do a decent fine grind, but you can't get a consistent medium or coarse grind unless you have a burr grinder.

Even a fairly cheap kitchen scale should be good enough to get a consistent amount of coffee, I'd start with 2 Tbsp (~ 10g) of beans for 6oz of water and adjust from there. Try more beans and see if a coarser grind gets rid of your clogging problem.

In general, a very fine grind combined with the extraction time you typically get in a pour-over will give you a bitter flavour. With the beans I've been buying recently, I use a fairly fine grind, but not as fine as I'd use for Espresso. Manufacturers of paper filters claim that they trap sediment which reduces bitterness.