Age may only be a number, but when it comes to the age of the universe, it's a pretty important one. Why?
Science progresses by explaining newly discovered phenomena that don't fit existing models.
When we discovered the Metushelah Star that looked like it may be older than the Universe it made us think harder about some assumptions, models and measurements we had.
The exact age of the universe is not that important but the early evolution of the Universe is an extremely important to our understanding of fundamental physics and may help in our search of the Theory of Everything