If Freddie Mercury was still alive

They would have remained fairly unsuccessful in the US, but not the rest of the world. Their Hot Space album garnered a lot of backlash here for being heavily disco-oriented (although "Under Pressure" is universally beloved), and it caused almost everything else they released in the '80s to become only minor hits in America, even if they were smashes elsewhere. The only exception is "Radio Ga Ga" (which did decently by reaching #16, but still underperformed compared to the rest of the world, where it peaked near or at the top of the charts) , although that was immediately followed by yet another US-particular backlash when the "I Want to Be Free" music video debuted on MTV and the meatheads here misconstrued the Coronation Street parody for the entire band being ultra-gay.

Regardless of their struggle in the '80s in America, Queen were still one of the biggest bands all the way through the mid-'90s, including their Made in Heaven album. "I Want It All" was a soccer hit, having entered the top 10 of plenty of countries, and even "Innuendo", which came out only months before Freddie Mercury passed on, achieved major success in numerous territories, despite its prog-rock length and complexity.

In America, Queen probably would have honestly done okay in the 1990s as a result of '70s nostalgia being prominent that decade, as well as the fact that the famous "Bohemian Rhapsody" scene for Wayne's World had already been filmed when Mercury was still alive, so the band still would have found a new audience in Generation X.