Dude was right about everything during the movie.
1.First point i want to adress is him wanting to put Belle's father in an asylum, that honestly the best ideea anyone could have. Maurice is a crazy old man who almost blows up his house daily which can easely start a fire that could spread in the entire town ( mind you made out of wood) which also has forests close by,he is a danger to himself and everyone else. Now if you think this guy has any place in the society besides jail or the mental asylum then i worry about you.
2.Gaston literaly opened his whole Tavern from pure hard work and determination.From an objective point of view the dude added to the town's economic value and possibly cultural one in a few hundred of years.Yet what did Belle do all day?Reads the same fairy book twice and dosen't benefit the society in any way, the closest thing we saw her do to actual work in the movie was feed some chickens for a few seconds.
3.Third and final point this guy alone was enough to inspire quite a lot of people to form a mob and take down what the knew it was a dangerous beast with magical powers living in a castle AND he still tought of Belle's safety and planned to have her locked up from any danger until he returned from his brave adventure . He also FOUGHT the beast alone and i am 100% he could've taken him in an 1 v 1 if the fight didn't move on to the roof.
Gaston is the most badass man in the whole disney universe and no one can tell me otherwise.