Has this been fixed by Bethesda? Like does it actually appear in the active effects?

I'm not sure to be honest but... would it really matter? The speech skill (and its skill tree) is almost literally useless and worthless in vanilla Skyrim, since to my knowledge there is not one single part of the game where you might need to rely on charisma or speech skill to get ahead. You make more money with higher speech I think but who cares? You already have enough gold to buy and fully upgrade the most expensive home in the game by level 15 or 20 anyway, as well as more health and mana potions than you can possibly carry.

I'd like to know whether or not I'm actually getting the benefit is why!

What in the world is the 'Gift of Gab'?

It's an English saying, it means being able to persuade anyone about anything.

It's a "supposed" passive perk that is thought to be awarded as...

However, I can't find any concrete documentation on it. I think it's just something mentioned in the Official Guide that didn't get fully, or properly, implemented into the game.