You only need a GmbH if you invest money, don't do that. You only need a notary for that. I didn't even need a second bank account.
- What you're talking about is working as a freelancer (Freiberufler), which is a subset of a sole proprietor (Einzelunternehmen); these are different business types than a GmbH, and the article is about setting up a GmbH.
- Only setting up a GmbH if you want to "invest money" is overly simplistic. People might choose a GmbH due to limited liability, a more solid shareholder structure, etc. Slightly more generalized, you do have a point that of course a sole proprietorship might be a much better and simpler choice for one-person "companies" who mainly offer software freelancing services.
- Not setting up a separate bank account for your business, GmbH or otherwise, is strongly advised against. Not only by literally 100% of tax advisors, but also by the tax office themselves.
That being said, even throwing money at a tax advisor won't reduce the 16 steps to 1. More like 5-10.
You'll still have to to go the notary yourself, you'll still be opening the bank account yourself, you'll still be subject to Handelsregister spam and fake invoices, etc., etc.
German system is more complicated than it should be, but I think this is a bit overblown because of the stereotype.
I wonder why German people often think they need to found one - maybe because people in the US have a low threshold of founding an LLC, but that's because it's easy and cheap; or maybe due to the German Angst of "I will immediately get sued, so I need limited liability".