Don't forget to weigh the fact that KF-21 is still an experimental fighter
It is still prone to delays, substandard performance, etc, ---> bigger risk
2. How can you say Rafale is not a diversification move (oc assuming it is one of the considerations) while you also mentioned the history of TNI being embargoed by RUS and US, and now we are being targeted by CAATSA----> It is better to have more than one option
Keep in mind that Dassault did withheld parts for the ROCAF's fleet of Mirage 2000s after being asked to by the PRC.
Personally, I don't really care whether we'll get F-16V or Rafale or whatever as long as it can be utilized by our air force, although I'm inclined to see the Russian option as something that will burden them more in the long run.
But still, whining about Prabowo and whoever in the parliament got benefits form his deal with France for Rafale does bring this into question: if our current MoD is not him, and the deal is not with France, can anyone really say that nobody in the parliament will reap benefits for their own from that?
Anyway, from the way I see it, the takeaway messages are these:
1. It's not only in Indonesia where military's preferences got squashed by politics. This happens everywhere.
2. As long as we source our military procurements from any foreign countries, there will always be chances for the embargo hammer to fall on us. This much is clear.
3. Thus, the best way for us to build our military strength other than expanding our own defense industries is by diversifying where we buy our arsenal from. Yes it will create supply chain and logistic nightmares (not to mention more chances for corruptions etc, especially if it's not being controlled and monitored closely) but I dare to say that's also one the consequences of our international politics standpoint.
4. In the case of KF-21, while most of its components (like jet engine, radar, other sensors and combat/counter-measure systems for example) are still out of of our capability to produce domestically, but this project is still way more valuable than just some 50 fighters that we're planning to acquire in the next 10 years or so. While it's true that we still don't know whether it will ready to be mass produced due to the possibility of delays and some other unforeseen problems, it still holds a very strategic value for us who desperately need to expand the capabilities of our national defense industries.