Very much not true.
The worst alternative by far are online charter schools
"CREDO’s 2015 study in coordination with Mathematica Policy Research and the Center on Reinventing Public Education revealed that students of online charter schools had significantly weaker academic performance in math and reading, compared with their counterparts in conventional schools." - https://credo.stanford.edu/our-impact/
"We found that students who switched to virtual charter schools experienced large, negative effects on mathematics and English/language arts achievement that persisted over time and that these effects could not be explained by observed teacher or classroom characteristics" - https://journals.sagepub.com/doi/pdf/10.3102/0013189X2090981...