Have you seen Ruby?
I don't know Python's innards well enough to understand why it's so especially difficult in this regard, but I gather around the edges that its object model may not be as well founded.
All just as dynamic as Python, and with quite usable JIT compilers.
Or for that matter, PyPy and GraalPy do exist.
Can you just replace CPython with PyPy or GraalPy in every project? And why not? :)
PyPy and GraalPy then never get to use those pseudo "Python" libraries, because their API for C based extensions differs enough that you cannot take a random shared library and load them into either.
They came up with a common C API proposal, but has hardly taken that much adoption.
JavaScript also has monkey-patching, and it's also very common. E.g. SolidJS replaces objects with dependency-tracking proxies.
There are really no fundamental language reasons why Python should be more complex. From what I heard from a JIT developer, the main issue is not the code itself but the module system and code loading.
JavaScript was designed from the start to operate inside a sealed environment with only few external handles, with the code loaded upfront or added on-demand via "eval". Not so for Python, where native code modules can (and will) result in code loaded dynamically and it's hard to track what depends on what.
Yet both languages are on the genesis of modern JIT compilers, going beyond what was already being done for Lisps, Prolog, BASIC.
And the proxies make it slow as Python. Plain objects cannot suddenly become proxies, so the runtime can treat them as a special case.
someone please think of the monkey patchers!