Would you agree if they will release a credit cards for all btc users . I think it can help alot to make transaction fast and also btc will be famous if that happens

For example you took 2 BTC with 8k per 1 BTC) In 1 year you should return 2.5 BTC with 20k $ per 1 BTC - it's extremely risky

So do not take credits in BTC)
You correctly noticed. It could just be the debt bitkoin pit. I do not think that there are many mentally normal people to take a loan in bitcoins. I would be scared.