However it's not clear at all that using old tools has the same effect.
Git development started in 2005, Fossil development started in 2006, they'ré equally modern, and largely do the same things, just in different ways.
I have some of my great-grandpa's carpentry tools, and I use them often. I guess I should go out and replace perfectly good tools with new stuff from a big store like Home Depot or Lowe's?
We dumped CVS because it was a poor tool, for the time. Subversion was better. Then completely distributed systems became better, because connectivity and computational power came about.