A tool shouldn’t need to come preinstalled with the OS in order to be useable. And “switch to a different OS” is not a good solution especially for cases where you don’t control the OS you run.
For a long time MacOS came with only Python 2.x installed. I looked up what the latest version of MacOS comes with and came across an Apple support forum post with several responses posting conflicting answers [0]. One person got an Xcode related error. Having to install a heavyweight IDE just to get a language to run correctly is the type of needless complication the parent comment is talking about.
xcode-select --install pulls in the CLT, which is a fairly reasonably sized download given that it includes various essential dev tools including python3 but without Xcode.
This is hinted at by attempting to run python3 before any install, which calls a stub prompting you to do just that.
py2/ruby/perl/etc... are part of the base OS for backwards compatibility/expectations (because they were so before Xcode/CLT were even a thing) but have been marked as due for removal from base for something like half a decade. My bet is that at some point they will move to the CLT (or some other optional download) as well.
For a long time MacOS came with only Python 2.x installed. I looked up what the latest version of MacOS comes with and came across an Apple support forum post with several responses posting conflicting answers [0]. One person got an Xcode related error. Having to install a heavyweight IDE just to get a language to run correctly is the type of needless complication the parent comment is talking about.
[0] https://developer.apple.com/forums/thread/691403