Well, you were free to install a version of Python3 on the CentOS6 machines, that's what we ended up doing and using for Ansible. Python 2.6 support of Ansible was a bad lie, multiple things broke already. 10 years of support without acknowledging changes of ecosystem just don't work.

we did, but then most ansible modules still didn't work on the system. They advertise the no-agent thing and how it does everything over ssh, and instead require python to be installed on all your servers because it generates python code and runs it on the remote machine. And somemodules require specific versions sometimes.