I am dumb. The more things I need to think about when reading code that is not the logic of the code, the worse it is. Any time I have to spend thinking about the peculiarities of the way the language handles something is time wasted.

I'll give a very simple example, think like you're trying to find a bug. Assume we're in a dynamic language that allows implicit conversion like this. We can write our code very "cleanly" as follows:

if(!someVar) doSomething();

-> ok, now we gotta check where someVar's value is last set to know what type of data this is. Then I need to remember or look up how those specific types are coerced into a bool.

When trying the same code in a statically typed language that doesn't do implicit coercion that code will fail to run/compile so probably you'll have something like this:

if(someVar.length() == 0) doSomething();

-> this time I can just look at the type of someVar to see it's a string and it's clear what the condition actually means.

The second option is both easier to read and less bug prone even without the type system. It takes maybe 3 seconds longer to type, but if your productivity in coding is that limited by typing speed then I envy you