2) Why do Bitcoin survive during crypto winter and other crypto's finds it difficult to cope ?.
I think you got the answer from everyone. But through this, I want to tell you, if you want to invest in the market, start and choose only bitcoin because it is the most valuable, most reliable coin to invest in. Bitcoin is the coin that will never crash and always recover the fastest in the market, and only when bitcoin recovers can the rest recover. If one day bitcoin crashes, I can assure you that this market will also cease to exist. If your investment doesn't include bitcoin in it, that's a serious omission.