The vocal uptilt --at least in common native-English dialects-- turns statements into questions, and/or indicates that the speaker seeks agreement or approval from the listener. Do it here and there and it's no problem. Do it for every sentence and it's very off-putting, and distracts from the content itself.

It's not radically different advice from not saying Umm every two words, not mumbling/eating half your sentence, not talking to a room in a whisper, etc.