Screen time for adults if baby present

Hi all! I heard it’s not recommended to use screens or tv for babies and young kids (they say until 2 years, but maybe this is an exaggeration!). However they also mention that even parents shouldn’t be watching screens or tv for adults with a baby. That seemed odd to me as surely in most households people put the tv on to watch a movie / the news whilst taking care of baby as they can’t be left alone, particularly at the start. Let alone other screens such as mobile phones which surely get used by mums when breastfeeding etc. What’s your views?