Speaking from experience?

Reddit is, as per definition, no social media, but a forum. On Instagram, Facebook, Snapchat, Twitter and probably Tiktok (I don't use it so I don't know exactly), people you know are suggested for you to follow/add. Likes are also often public. Reddit is way more anonymous. If you fuck up on, let's say Twitter, by saying something controversial, people are gonna remember you for that. That works for both good and bad things. Your history on Reddit is way less important than on other sites. If you get up- or downvoted depends on what you say, not what you said.