I'm not gonna discuss other country's laws. Whether they go or not isn't my business.
However, the statement that you made "The only reason BTS is given it today is because politics deemed it something that can benefit them for today's younger generation of voting public." is something i don't agree with at all.
BTS's impact is the sole reason why they are being so heavily considered. And none of the groups you mentioned have that impact. So no, they didn't earn this as much as BTS.
The fact that there wasn't even a discussion about exemption when others enlisted is enough proof.
However, military exemption can’t be just be judged by government. It is the law and they have a system to determine who are deserved for exemption and how it applies to everyone. The same for sport, maybe they require certain award in music for exemption. I can see something like BTS got a Grammy may sound more reasonable. There was a discussion from military about No.1 BB and how they found the achievements doesn’t sound good enough for exemption, considering how their No.1 was funded by oversea fan to bulk buy their music in the US.
Back in 2019, superM can score an inorganic No.1 B200, so are they deserved for exemption? Back to now, BTS score No.1 BB100 with fan manipulation sale, got heaps of backlash from media. Very similar story with SuperM in 2019.
Also, Culture impact/ economic contribution doesn’t sound like a proper requirement. Bigbang, EXO, DBSK and many Korean actors led the way for first and second Korean wave, they should deserve the exemption as well, but they did not. The first and second wave helped Kpop spread through Asian, it was a huge achievement 10 years ago. Economic contribution also controversial, if BTS contribute to SK economy, how about CEO of big SK companies? Samsung LG CEO, director , creative team also contributed to SK economy, should they be deserved exemption?