I don't have a strong opinion what is better in this case, but my view is:
> document and express intent clearly
Arguably, the void* does that as well?
> Any seasoned C++ developer seeing this knows what this reinterpret_cast means.
Same for void*?
> it's a bit more text to read
If you have to call it many times, this adds up.
> Some might also say it complexifies and uglifies the code
I think the point is that it adds security, which the other options don't. And, it doesn't add complexity on the caller, but only at one place: the implementation.
> makes it non-portable on top of that.
This can be solved.
> document and express intent clearly
Arguably, the void* does that as well?
> Any seasoned C++ developer seeing this knows what this reinterpret_cast means.
Same for void*?
> it's a bit more text to read
If you have to call it many times, this adds up.
> Some might also say it complexifies and uglifies the code
I think the point is that it adds security, which the other options don't. And, it doesn't add complexity on the caller, but only at one place: the implementation.
> makes it non-portable on top of that.
This can be solved.