As you can imagine, no one will be able to tell you anything about restrictions lifting - and since you are not travelling until December; I honestly wouldn't worry about it much until closer to travel date. So much can change in just a matter of days!
Specifically on your question re: transit in SCL; your bags will not be checked through as far as I know. You will have to clear customs upon arrival in Santiago and recheck the bags, before you can proceed to IPC (a domestic destination).
2.5 hrs is tight, but not impossible (and certainly within MTC given this was sold as a single ticket). It is very likely that flights will be retimed between now and December, so just keep an eye on your itinerary.

I have very fond memories of my trip to IPC - one of my favourite destinations in the world!