MSET is the DS Profile exploit. The only thing downgraded to enable it again is the settings app.Just the settings app? And downgrading it would renable the MSET exploit on firmwares as high as 9.2? I'm pretty sure that the NATIVE_FIRM patched part of the DS Profile Exploit as well, so there's got to be more to it than just the settings app, right? Or is this downgraded MSET exploit gonna work differently than the DS Profile Exploit?
MSET was finally fixed in 7.0. So, you're probably thinking of the ARM9 hax used in 4.x.
Kind of like getting ARM11 Kernel/ARM9 through Cubic Ninja or OoT. And Spider, MiiPlaza as well, I guess. They're all just entry points for other, more powerful exploits. And you could technically also downgrade Spider to reenable but mostly pointless as you'd already have a way in the system if you're able to downgrade random titles.