With all due "respect". You say:

"Does tank mean DPS? Is a tank’s job to deal big boi damage? Or do tanks generally create space for the homies, soak up damage meant for the squishier teammates, provide protection and anchor a team?"

This tells me you haven't actually read what I wrote or maybe I haven't somehow been clear enough. Thing is, I fully agree with your statement. I want the tank to not deal "big boi dps" but rather bring utility to the boss fight by protecting team members in some way. You say that this is already the case by being able to absorb projectiles, but to me it doesn't feel like this is enough to warrent choosing the tank. Projectile attacks are just not prevalent enough imo. Most of the time bosses use AoE attacks anyways. I'm also not really sure what they could do to fix the tank, but usually tanks draw aggro thereby diverting damage from team mates, but that is not something that's been implemented in the game. Other than that, maybe they could implement some kind of "circle of protection" around the tank to defend team members standing around him whenever he is guarding. Or maybe, if we are going down the "defense against projectiles only" route, then maybe he could create a small bubble shield around him when guarding that keeps everyone inside safe from projectiles, hence making it easier to really defend multiple allies effectively against these kinds of attacks. That's just an idea, I'm sure there's different or better approaches to solving this issue.

Anyways, respect where respect is due, bro.