Tacuaches literally refers to 'possums'. However, in Mexican slang, it's often used to describe people who are uncultured, unsophisticated, or lack ambition.
In the song, the artist states, "Con gente grande, no me rodeo de tacuaches" (With important people, I don't surround myself with 'tacuaches'). This line highlights his rise in status and his desire to associate only with successful and influential individuals, distancing himself from those he perceives as beneath him.
El Rabbanito spends this song watching other people react to his money. It opens on their faces — "La boca abierta les quedó" ("Their mouths were left hanging open") — and the rest of the song is a list of what put them there: a Cadillac loud with corridos, Christian Dior on his feet, a yacht off Miami, business closed in New York. He is careful about who gets the credit. "No lo hice solo, pues cargaba un equipón" ("I didn't do it alone, I was carrying a whole crew") lands early, before any of the boasting, and he comes back to it when he says he keeps company with "gente grande" ("big people") instead of "tacuaches" — hangers-on who show up once the money does.
Underneath the flexing is a working man's logic. "Tengo cabeza, por eso estoy generando" ("I've got a head on me, that's why I'm earning") credits thinking rather than luck, and "La vida es corta y al toro hay que brincarle" ("Life is short and you have to jump the bull") is the nerve that goes with it. The quietest image is the one he repeats: the sun dropping behind the balcony, and "prendo uno de Mary" — lighting one up at the end of the day, with nobody watching. He closes on "Tengo poco tiempo pero doy paso certero" ("I haven't been at this long, but every step lands"), which is as close as he comes to explaining himself.