According to the latest data I could find, 2022 had the lowest rate of uninsured Americans on record: https://www.kff.org/uninsured/issue-brief/key-facts-about-th...

There were some pandemic era programs that increased the number of insured people, so it is possible things have changed since 2022. Either way, there is no evidence that the repeal of the individual mandate actually resulted in less people with health insurance.