Any dates or information on when this could happen and what it would look like?
I don't care a centralized government entity in one country does to a bunch of centralized shitcoins.
What are the possible effects on bitcoin price? Could the price possibly shoot up if everyone is forced out of stablecoins?
Did bitcoin price shoot up when a lot of countries around the world banned ICO scams? This would be the same. Altcoins and what happens to them has no effect on bitcoin, specially when they are centralized altcoins.
I feel there will be something that causes a decline in bitcoin nearterm,
We can never predict what they panic-y newbies are going to do. They may start panic buying!
this cycle has been longer than any other already
No it has not. It is not even as long or as big as the previous one.