I personally believe Horikoshi is killing villains because the current roster srsly can't match up against Bakugou, Deku, Todoroki and other rising stars. If you compare power levels what Compress says is true, he doesn't cut it in terms of power. Horikoshi knows this and must make room for more powerful vilains.
Now, Compress was a bad ass this chapter. I am personally sad he will die because the dude had potential to be amazing. His design is awesome, his backstory could have been amazing. But like he said , he lacks power and right now he did what he does best - escape.
Spinner is a lose end here. I don't know what his deal will be but we will see.
Now, With Twice dead, Compress dead the LoV will have to replace numbers. This war was costly and they will need to replenish troops. Tartarus is beyond amazing target for that.
I think in the next arc we will get far more stronger vilains introduced