What exactly did Garrosh do that everyone dislikes him and what happened with Thrall that everyone calls him Orc Jesus
RIGHT, so, first of all, Garrosh Hellscream is Grommash “Grom” Hellscream’s son. Grom Hellscream is a HUGE fan favorite, and a really important character throughout the ages of the Warcraft franchise, starting with Warcraft II and culminating with his heroic sacrifice in Warcraft III. Both in and out of universe, Grom is A Big Deal. Grom and Thrall were best friends, and though Grom is Thrall’s senior in rank, age, and skill in battle, Grom respected Thrall’s wisdom and bravery, thus he followed him and what he intended to build out of the Horde. Grom is also the Chieftain of the Warsong clan. His final sacrifice freed the orcs of the demon’s control once and for all, striking down the Pit Lord Mannoroth and dying in the process, a foe Thrall could not even injure with his attacks. That’s like a very short summary because lore gets EXTENSIVE. All in all, Grom basically fucked up because he willingly gave himself to the demons for power twice (in WCII and in WCIII), but he fixed this himself after being shown reason, killing the demon with his own damn axe.
Now, here’s a thing you need to know about Thrall, and why we call him Orc/Green Jesus: He’s a very, legitimately good guy. He wants nothing more than peace between Horde and Alliance, he wants to distance the Orcs from their past as Demonkind pawns, he wants to work hand in hand with the other races. Debuting in Warcraft III as the Orc protagonist, Thrall used to be an orc, well, thrall (another word for slave) that was raised by humans that killed his tribe and brought him back, himself a baby at that time, with them. Among Orcs, Thrall was particularly massive and strong, but also very smart. Being taught by humans, Thrall eventually escaped with the help of his human friend, Taretha Foxton, the daughter of the human wet nurse that nurtured him in captivity, and sought out the undefeated Grom Hellscream after learning about him from an orc in captivity. Grom told Thrall that he was from the Frostwolf clan (he knew this from the patterns in his tattered clothes), and sent him to where the remaining members of the exiled clan lived, and he also taught him the Orc language. Thrall, once he arrived to where his clan was, was revealed to be the son of Durotan, the Chieftain of the Frostwolves, and there, a frost wolf (massive damn wolves), Snowsong, chose him as her companion (she’s his mount). Thrall then made communion with the spirits of Wind, Earth, Water, Fire, and the Wilds, and became friends with them, becoming the first Shaman since the end of the First War (Warcraft I), as the Spirits had condemned the orc race after Gul’dan (yes, that mother fucker) corrupted the entire race and turned them into demonkind pawns. After this, he’s put to the test by an anonymous Orgrim Doomhammer (you know, Warchief of the Horde and final orc boss of Warcraft II), who approves of his strength and, during a liberation of orc captives later, names Thrall Warchief after dying in that fight. Then everything in Warcraft III happens, and man, THIS big paragraph is a VERY short summary, because you can talk about Thrall all day, a LOT of lore, but basically, he’s like ultimate chosen one and fully deserves that position. The last thing you need to know about his Green Jesusness is that the amazing, amazing last level of Warcraft III: Reign of Chaos can be summarized as “Thrall, Jaina, Tyrande, and Malfurion all put their differences aside and make the strongest team fucking EVER to stop Arthas, Kel’thuzad, and Archimonde’s Wild Wild Ride”, and the alliance between Orcs, Humans, and Night Elves here could only happen thanks to Thrall’s efforts (as well as some help from Medivh).
Then we have Garrosh.
Garrosh Hellscream eventually rose to become Thrall’s successor as the Horde’s Warchief. Thrall had high hopes for Garrosh, first appointing him as an advisor and then personally stepping down so Garrosh would become the Warchief. The first thing he does is basically spit in the face of every single effort Thrall has spent trying to prepare the Horde to make peace with the Alliance. He hates the Alliance, and wants to kill every single one of them like some mustache twirling miscreant in a black top hat. He goes and initiates the invasion of Pandaria (where the funny panda people, Pandarians, like Chen, are from), and during it, unleashes the Sha of Pride, basically a super-sealed evil who spread corruption and death across the entire continent, eating the souls of countless people. Later, he deployed a weapon called a Mana Bomb in Theramor, a Human Bastion in Horde-controlled territory, with which the Horde, due to Thrall, openly traded with. This was the deed that made even super traditionalist and cruel members of the Horde who want to just kill the shit out of humans say “hey what the fuck man”, and the last straw was broken. Garrosh literally nuked civilians. At that point, Thrall himself rallied the Horde against him, and he was accused of war crimes (of COURSE he was). The first time around, in Pandaria, he was sent to trial, but he escaped, and the second time, Thrall himself challenged him to a one on one duel, and killed the fuck out of him. Garrosh was stronger physically, but the thing about Thrall is that he’s also a really powerful spellcaster, and thus Garrosh died by being grabbed by giant earth hands and then struck by lightning.
TL:DR: Thrall is basically a nice guy who is just trying his best help out and Garrosh is a literal war criminal who nukes innocents.