Sudden loss of power when shifting or sitting at a light, can't idle (motorcycle)

After hitting a nasty bump on the road a month ago, which stalled my bike immediately, the engine will occasionally go from providing normal amounts of power to about 25% of that power, and it will stay in that low power state for a seemingly random amount of time, could be 30 seconds could be 10 minutes. The engine will make a deeper noise when it knocks into that state, and it will have to rev to 4-5k RPM to get moving to 10 mph, normally something it could do with 1-2k rpm. Basically making it slow as hell and unridable when it gets like this.

It used to happen once a week, then once a day, now the bike cannot even get down the street without running into this low power state. It consistently happens when stopped at a light or going down a steep hill.

I know the problem was caused by the bump but I don’t know what it did. I replaced the spark plugs, recently cleaned out the air filter, exhaust is coming from both pipes when it’s like this so both cylinders should be firing. My bike is carbureted and google searches are leading me to believe there might be a problem there, but I have never pulled carbs before and am not sure what mess I’d be getting into. A couple days ago I sat on my bike to try to figure this out and the headlight and taillight wouldn’t turn on, so there is probably a wiring issue somewhere. Could that be related to this low power problem?

Looking for guidance on what part / area of the bike I should be troubleshooting to narrow it down. Does it sound like a carb problem? Electrical? What can I do to eliminate some potential causes?

thanks
1980 gs250t