No, under fiat you don't need to print extra money for the interest, the debtor just needs to perform some extra economic activity. The interest money comes out of extra cycles in the circulation.

The interest is a consequence of time preference and not a bug of the system.

Inflation rewards keeping money in circulation instead of hoarding it.

Without loans the economy would move incredibly slow. I can get $10k or $20 instantly tomorrow from the bank and much more with some formalities.

If I had to earn the money first it would take a long time.

That the government can lend money into existence is an additional feature in addition to bank loans but not a requirement of the system.

If you can't borrow Bitcoin, people and businesses would have to use what little they have.

Also deflation encourages hoarding which will remove more Bitcoin from circulation which reduces the Bitcoin supply for the economy which causes more deflation in a vicious cycle.

We all understand that and see that bitcoin is doomed from the get-go, in addition to all the implementation problems.

No Bitcoin person has ever attempted to run the tiniest of business. Not even a cafe at the corner. That's where their delusions come from.

Silvio Gesell wrote about all that in The Natural Economic Order.