That's a very old ignorant view. It probably was more true for a time, many parents didn't wanted their kids thinking Jesus rode dinosaurs, etc. But ultimately even then, in a few cases that didn't hold them back, they usually got into adult hood figured out their parents were likely full of crap in college, but because they also learned math and reading, and did often better, which is actually something needed practically and were successful as a result.

Many modern home school curriculums are secular are taken from the same ones or follow the same standards/guidelines schools use. Majority of home schoolers I know are secular, and want better options, especially those to meet the learning needs or styles of learning they themselves or their kids thrived in. They don't believe either because their own experience or what they've seen with their kid that kids learn best in a very rigid, sit down, and be quiet and listen model of instruction that was designed for factory workers and has barely changed in 100 years.

Also, there's nothing stopping a parent from putting a kid a private Catholic/Jewish/Orthodox/etc school, etc that will do the same. Parents can indoctrinate their kids, home school or not, into a religion, they have them on evenings and weekends where the ultra religious just take the kids to their religious institution 4-5 times a week.