The Eastern Front showed how much tanks could and couldn't do. They could use speed and hitting power to destroy organized resistance. They couldn't win Stalingrad.

Tanks have a continued role in warfare so long as they can operate in their 'zone'. Unless your entire nation is a city, tanks can kill people just as effectively as a regular soldier.

Tanks will continue to fight so long as they are useful. You don't see anyone not investing in tanks because they can't operate in urban situations. They are still used and bought because they can operate where infantry can't, like open fields.