Really not true.
Low bar squats performed with poor form are certainly likely to lead to injury, but performed correctly they are fine. Other types of squats like high bar or front squats are definitely not a problem for the back.
In fact, more back injuries come from poor form deadlifts than squats, guaranteed. When deadlifting in conventional stance, it is insanely easy to develop bad habits by breaking form to essentially muscle up weight that you can't lift safely. When doing so, it's your lower back that gets shit on. Same thing with poor executed Romanian deadlifts or rows, but they can't be overloaded with as much weight.
Form is what matters. If you lift only what you can lift with proper form, you're unlikely to get injured. Done correctly with proper core bracing, these compounds lifts are safe and will make your back strong as ****.
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