Salty should definitely not be a taste in coffee, unless you're tasting the very first few drips of a cup of espresso.

Proper espresso extraction curve looks like this :

• Salty and very thick (very first drips)
• Sour and thick (underextraction)
• Sweet and chocolatey (the sweet spot where extraction should stop)
• Bitter and suddenly very thin (overextraction)

Properly extracted coffee should let sweetness dominate. Acidity and fruitiness should be still present for pale roasts, but not sourness. Bitterness should not dominate and if so, it's a flaw. Means you overshot the extraction. Which is very easy to do with shitty burnt coffee as darker roasts are much easier/faster to extract.

Sourness and bitterness present at the same time is a big flaw, means that the extraction was very uneven as part of the coffee was overextracted and part was underextracted.

The thing is tho, great coffee is expensive. Good beans properly roasted by a reputable roaster are expensive. Proper preparation skills needs learning and experience. Proper gear is relatively expensive (even at the lower end of the scale like an Aeropress and a good mid-range burr grinder). Most people don't want to invest the time and money it needs to get great coffee each day.