Ambiguity and obfuscation are usually intentional. Legislators and individual citizens do not necessarily have the same interests. This is why omnibus bills exist.
And they are updated quite frequently and implemented quite programmatically!
But the laws also remain ambiguous because the world is an ambiguous place with a lot of edge and corner cases with unforeseen knock on effects.
That said, one would hope
1) the tax code would be one of the least open-to-creative-interpretation parts of the system
2) the IRS equivalent could actually produce this code, rather than legislators