Like most of his música mexicana contemporaries, Diego Millán, better known artistically as Calle 24, sang about the excesses of living the rock star life — the money, the cars, the booze and the women. Since signing with Street Mob Records — the independent label founded by Fuerza Regida frontman Jesús “JOP” Ortiz Paz — in 2020, the singer-songwriter has been responsible for hits like “Que Onda, ” which featured labelmates Chino Pacas and Fuerza Regida. The trombone-laced earworm about a deboucherous tryst was a breakthrough for Millán, reaching No. 61 on the Billboard Hot 100 after it debuted in August 2023. These days, the 23-year-old Chihuahua-born artist is dialing down the glitz, opting for songs that aren’t about living the luxurious life. “Money brings more problems,” Millán tells me inside an Italian restaurant at the Americana at Brand, Glendale’s monument to opulent consumerism. “Because the more money you have, the more things you have to support.” In April, Millán released “Eterno,” his fourth studio album. The 15-track LP largely forgoes the boisterous brass section …