Brothers, i need the Bulwark mains to explain

So im not the greatest as parry/dodge granted, but why is it that every video and every guide claims tht Bulwark is this unkillable tank when that simple isnt the case? maybe when you have maxed out at prestige 4 lvl 25, maybe, but sure as Horus not while ur leveling it. or have i missed where the magic perk tht makes bulwark unstoppable is?
It's a shame in any case cuz Bulwark is probably my favorite class besides heavy or sniper, but with bulwark its more frustrating and irritating than fun to play, which makes it so much more frustrating when u read or hear ppl say its an "ez class" to play, like no, no it aint, maybe for you but then why not play bulwark if its so easy to play?
idonno, i wouldnt say its a full rant, im genuinely looking for advice, but its frustrating as hell.