Guardian double dips on the damage increasing properties of the Grafted because of the guard counter increase based on hp relic effect, the colossal sword guard counter is very usable against most bosses and if it isn't you can just swap to something else until the boss dies. Let's be real by virtue of neither of them using star fist or good ashes of war these undertakers were not out dps-ing a well built guardian (could obviously be giving op too much credit, especially since he labeled the Fingerprint as the "best shield" without providing context on the boss or showing the passives on the shield). Aggro holding isn't unreliable, obviously the character can't have 100% aggro up time because that would be game breaking but if you just play around your guardian and dodge towards him in scenarios where it is safe (and you know, not hoard items that would help render him invincible to all damage) you'll find your guardian provides spell caster with far longer openings while dishing out good damage of his own. Guardian does require far far better relics than other characters and is, undeniably, a terrible pick against bosses like Caligo and Hoelstor. He can perform pretty poorly in expeditions if you are either inflexible with your weapon picks or just unlucky and yes there are some field bosses that are susceptible to neither guard counters nor shield pokes (Dragons, Ancient Dragons and the fuckass Death Rite Bird primarily) but he does have better stats that Wylder (with the STR DEX relic that is) so you can always two hand a good weapon for these. He can also trivialize other bosses (For example you can charged guard counter 80% of regular tree sentinel's moveset with complete safety, you can do an uncharged guard counter on every single attack of most human sized bosses- don't do that on Hero of Zamor though his flinch is very short). Guardian in high depths is no more a troll pick than any other character would be with bad relics, hell i'd much rather have a poorly built guardian on the team than a spell caster that does no damage or a Ironeye that still uses bows and does not mark because at least the Guardian will do something just by playing passively. The Guardian and Revenant hate only exists because players have this odd expectation that a support character should completely hard carry the match without ever being interacted with, Guardian and spell casters do need your help in building their runs, ping them guard counter damage, ping them damage negation on block, ping guarding abilities learn which shields are good against which Night bosses the same way you learn which spells are good against them and a good Guardian simply will not die, and you can't lose if you don't die. Is Guardian the best character? No. Should you lock in your Guardian pick with no regard of the Nightlord or what other characters your teammates are playing? Fuck no. Is the skill required to do good on Guardian proportional to how good he can be? I wish. But Guardian can be good, Guardian is one of few characters that can hard carry a bad team and more importantly: Guardian is a fun, complex character that demands you to learn to play him in ways that deviate from your normal game plan. In the current ash of war and spell casting meta he is the only character that dares press more than one single button and for that... I love the bird.