Right now businesses take loans for a lot of reasons, not the least of which is that government and fed policies heavily subsidize lending and have turned the entire financial system into a giant ponzi scheme.
The problems you are describing would be real if a businesses in a Bitcoin-based economy behaved like they do in a dollar economy. It's false to assume that the way things work now is the way things will always work after a paragidm shift.
Oh enough with the bullshit. You are wrong. You either have no concept whatsoever of how the economy works, or you are just purposely turning on the blinders so that you can find some rationalization for bitcoin's economy. "LOL THERE'S NO NEED FOR LENDING LOL LET'S KEEP SOCIETY AS IMMOBILE AS POSSIBLE!" What you want is feudalism. AIN'T GONNA HAPPEN. The economy would grind to a total halt without lending. Lending is beneficial to both parties; people have money that is idle and want to increase it, other people have ideas to create or expand the economy and need money. You. Are. Wrong. Totally. Absolutely. Wrong.
I am trying to make a basis in reality whereas you want to pretend that there will be 3%+ interest rates in a deflationary economy. Yes, inflation encourages investment, and likely over-investment, but you are trying to argue that there will be at least "enough" investment to encourage growth by assuming that there will be a positive nominal interest rate that can be had for low risk in a deflationary economy. Except that there are big issues with that that you want to ignore.
Uhh, I did no such thing. "Real growth in the economy as a whole when businesses borrow money makes businesses prone to go bankrupt. In real terms, loans get harder and harder to pay back." I am assuming real growth causes deflation, thus making it harder to pay back loans. Where is the contradiction? Oh, doesn't exist. The problem is that deflation will stunt growth, and yes, there may be no deflation at all because nobody wants to risk borrowing bitcoins and thus no growth. The point I was trying to make.