There is no wrong in doing so:

Python max() Function

The max() function returns the item with the highest value, or the item with the highest value in an iterable. If the values are strings, an alphabetically comparison is done.

OP solved it, closing

The description doesn't say it.

What will happen if someone has a two part name, like von Braun? Or it will include some tags, processed afterwards, that should be not capitalized?

You're overthinging it :)

How exactly it matters? say_hello('john') => "Hello, john" would be an expected behavior.

Note: math.pow and some others math functions are disabled on final tests.

It does say they're disabled so you have to find another way to do it. And it has Restricted tag. Not a kata issue.

1. The reason is that i value is not incremented in a loop, so i remains 0
2. Actually in Python there is a more simple for loop. In this case there is no need in any counter

Not a suggestion.