yes it is true. when i had my tama when it was a baby i went on tamatown for an hour and when i came back the tama still didnt evolve. so i guess that its like on pause when you go to tamatown
The Tamagotc v6/Music Star instructions clearly state that your Tamagotchi is in pause mode while on TamaTown, going "Out", or connecting to other Tamagotchis.
Well if you leave it on the Log in password for a while, it pauses your TMGC. So I recommend if you write down your user name & log in passwords in a notebook or piece of paper, that's what I do.