The reason US is resuming arms sale to Indonesia is because
Indonesia is now actively looking for other sources/ other
countries to diversify. Even with the resumption, Indonesia won't
exclusively depend on US so much anymore, to avoid getting blocked
again in the future if some political dynamics change again.
Basically it's more for sophisticated stuff like airplanes
spare-parts. Now so many of Indonesian airplanes can't fly because
there's no spare parts. Indonesian military is pissed off and
decided to search for other sources for arms purchase. Recently
they bought Sukhois. Seeing this the US lifted the arms
embargo.
By not selling sophisticated arms, US won't achieve anything. Does
it mean if US won't sell fighter jets, Indonesian military will
reform itself? So as to become an eligable buyer? Indonesian
military will simply find other sellers.
Second reason, right now the democratically elected Indonesian
president is also combating terrorism. In other words, there's not
enough black-marks to continue to stigmatize. He's combatting
terrorism and he's democratically elected. Plus, the reforms in
Indonesia in other fields.
The reform in the military/ intelligence itself will definitely
take time. Definitely it hasn't been completed.