In the 1980's we lost a lot of F-16s in the Utah desert because some idiot thought that the F-16 could do close ground support.
Oh they got close to the ground alright. In 1982 one half of all the F-16 crashes were at the UTTR. I scraped up way too many Americans out there.
The A-10 is an excellent example of a weapon system designed for one mission. It is a one-trick pony but it does that one trick very very very well.
There is nothing wrong with specialized mission aircraft. Unfortunately due to mission creep, contemporary aircraft have to be multi-mission despite the incompatible requirements. We end up with very versatile aircraft that can do an "OK" job for many missions.
The A-10's mission is to destroy things on the ground. To literally make tanks go away....and bring the pilot back alive.
Those are two pretty good missions in my book