I believe it’s also correct that Egyptian, Sumerian, Chinese and perhaps Harrappan were known to exist before the time Babel was supposed to happen and certainly Babylon (with the Tower of Bab-el -Marduk) was built far later when many nations with different languages existed.
As for the oldest languages in the world based on the first written account:
Egyptian – 2690 BC
Sumerian – 2600 BC
Canaanite – 2400 BC
Chinese – 1200 BC
The tower of Babel is older than these.
“Some scholars use internal and external evidence to offer 3500–3000 BC as a likely range for the date of the tower,”
https://en.wikipedia.org/wiki/Tower_of_ … r_of_Babel
So, your claim would be false and the tower of Babel would precede Egyptian, Sumerian, and Chinese.