I think it's appropriate to again stress that Thor is a true Alpha male - Conor is NOT an alpha male by the truest definition. Modern society helps a manlet like Conor ascend to 'alpha male' status, through celebrity, money and having the UFC as a platform, but he is still a 5"8-9 sub 200 pound beta male in comparison to Thor.
People are questioning Thor's ability to make use of his ridiculous physical advantages - here comes the bro science - Hafthor like all true alpha males naturally can fight, are extremely aggressive and competitive. Coupled with the fact I'm guessing from what I've seen Hafthor, like most men, are fans of combat sport and has watched plenty of fights - so it's a case of monkey-see-monkey-do; I'm pretty sure Thor can put some rudimentary techniques into practice even w/out training.
If you put Hafthor in a real fight with a beta male like Conor and Thor went beast mode, Conor would be in serious danger of legitimate injury.
This fight should NOT take place for health reasons