The argument for buying a budget flagships is more about common sense than anything. You are getting all the power of a the best phone money can buy, without having to lose an arm and a leg in the process to pay for it. In that sense OnePlus has been king. The company has taken the US by storm with their most recent launches, and the OnePlus 7T marked a more aggressive approach where a lot of the fluff of the 7 was removed in order to shave the price. 

Source: Youtube