In a history of running ansible for ages against 5k-25k machines regularly in not a single case I had to install python on any one of those before running a playbook. There's a reason why it's described as agentless.
In fairness, there are some dependencies depending on what you're doing; ansible's use of apt needs python-apt (or maybe aptitude?), and I have hit that one hard (granted, on termux, which is a weird target). Oh, and I had to do the equivalent on Fedora. Which is fine, mind, just pointing out that dependencies do still happen in ansible.