Yes If your reputation is below the red zone means below 0 then it can take your post to low hidden rating posts and comments. As there are many account who are taking their reputation to even -1 , -2 and many more. This happens when you are copying continuously some one posts and comments or you are doing misuse of Steemit platform and then the higher reputed account which better SP then you down-vote your account, This takes your account or reputation to below zero if continuous this things happens.

People who has less reputation may be a scammer and cheating with many other users in blockchain so this account goes to down-vote by other and with this their post and comments are automatically hidden by steem blockchain.