In Vanilla that's intended, because if you pick a Mythical or legendary to a dungeon that restores the level to 1, you will start with your stars so high in comparison to any other Pokemon in the first floors of the dungeon
But, your starter could barely have any stat on +10 if is any other species
And, in Vanilla, you obviously don't have mythical/legendaries for starters but you are playing randomizer so anything could show up as an option for you