If Zero was a natural born citizen he was never of age to renounce his citizenship and would remain a US citizen no matter what Indonesia said or thought. This is a dead letter. US law supercedes any foreign law wrt to citizenship.
If Obama was born a natural born citizen he would have ended this masquerade months ago by presenting the evidence to shut up his distractors.
If his Indonesian step father adopts B, he reverts to the Indonesian citizenship. Check the adoption laws of the US. You are right, parents cannot take away your US status, however adoption changes the situation. Otherwise, if BO is 18 years old, can the US draft him for military service (assuming US draft still existed) and arrest him for draft dodging and come after him for any US obligations if B never left Indnosia????