Not an issue

There is no issue. The kata explicitly states that .25 should be rounded up. The top answers you see work in python 2 before python changed the way round() works in python3, but that doesn't mean the kata requirements are different.

Without knowing the exact context of the language and kata you're talking about it's hard to say for sure, but it does make sense since print() and return should have different features.
print() prints the output to console (so that we as the user can read it) while return actually returns the value to whereever the function was called. E.g. the function
int multiply (int a, int b ){...} (in C++)
should use return so that in other places of your program you can use statements like
c = multiply( a, b );
and c will actually be assigned the value a times b. If you used print() inside the function, then that value would just be printed but not assigned to c. The test cases most likely check for the return value of the function, so print() does not fulfill the test conditions.

I've got to rank 5 kyu when I was around 310 honor, and that was doing mostly 8 kyu problems with a sprinkling of higher level problems.

Your rank is not exactly based on Honor. How quick you reach 5 kyu depends on how difficult kata you solve. Some info can be found here: https://docs.codewars.com/concepts/gamification/ranks/#leveling-your-rank

But you can generally observe your rank progress circle in your profile so you will know how far from 5 kyu you are.