The "All I Wanna Do" singer didn't hold back on Twitter Wednesday morning about Jason's single, "Try That In A Small Town" ... which talks about bringing anti-police and anti-American views to a small community, saying "See how far ya make it down the road."

Sheryl, who says she is from a small town, thinks people in places like that are also tired of the rise in violence in the country ... calling the song "lame."

She adds, "You should know that better than anyone having survived a mass shooting."

For those unaware, Sheryl's referring to the horrifying 2017 Las Vegas shooting at the Route 91 Harvest music festival -- Jason was performing when Stephen Paddock opened fire on the crowd from Mandalay Bay.

As we reported, Jason's been receiving hate over this track ... and he responded to the communal noise Tuesday, saying the idea that it has racist and hateful undertones is BS.

Folks were pissed about his music video, too -- which was shot in front of the Maury County Courthouse in Tennessee ... the same place where 18-year-old African-American Henry Choate was lynched in 1927.