You're comparing a surgical scar in your abdomen (which these days can be done pretty minimally invasive in some cases) to unpredictable tearing into the perineum (and in extreme cases even into the rectum), not to mention likely complications from birth like (temporary) incontinence.

I wouldn't advocate for routine c-sections and it is still surgery with all the risk that entails, but if you're not generally prone to scarring, the optimal outcome for a c-section can be far more predictable and doesn't have to involve a "huge scar over [your] guts".