> if it's _truly_ agent-less why do they care about the python version on the target, I feel that python target code is the agent?

"Agentless" means that it works by pushing to the machine and that there isn't an agent process already running on the target. It doesn't mean that there aren't any requirements on what needs to be installed on the target already.

It can do truly agent-less using raw mode (which is basically raw SSH). That said a version of Python 2 can be relied upon to be available on almost all Linux box.

yes that's what I used as my target is a resource-restricted router that does not have space for any python, that's the only occasion you can call it agent-less, but most people are not using that mode.