Same price point, except that credit cards usually cost extra here.

Since bank transfers are immediate now (unlike in the past when monthly batching was cost effective) and most credit cards in Germany are managed by the banks and coupled to bank accounts, they could just reconcile all transactions immediately (and even reject those that overdraw too much).

In such a situation, credit would become a risk adjusted premium feature and you'd have to calculate if it's worth it (vs the bank's regular interest rate on overdraw).

Plus, according to the OECD Germans have somewhat higher household savings (relative to household income) than Americans, so the liquidity might be comparable without using credit.

You are missing my point. I don't care if credit reconciles immediately at the bank level or not, I care about what credit cards allow me to do, which is smooth over lumpy cashflow.

If I have expenses of 100K a year, without access to credit I have to make 100K a year without fail, or I am insolvent. With credit, I can make 100K one year, 0 the next and 200K (+ whatever interest I need to pay for Year 2) in the final year. The optionality is more than worth whatever interest and surcharges I encountered by using credit in Year 2.

Lest you think this is insane, this is how I bootstrapped my last business.

If it were insane nobody would do it. It does, however, come with a magnitude of risk that Americans seem more likely to accept than Europeans are.