I think you just summarised one of the core issues of the discussion that happened in this thread: the presence of that "fear", i.e. lack of trust, which is directed towards both the product and the platform.

If a product is buggy, there's tech support / specific forums. If the product is buggy and this issue is not addressed over time, its reviews will fall down to 1 star, which will kill its sales, which will effectively protect new customers from investing into a buggy game. On top of this, there's the refund policy, which allows to return the game that's buggy / does not work, without much hassle. So what's to fear – if the platform's built-in mechanisms provide enough protection against the products that might indeed have a problem?

A second observation is that if you value the offline version, then why compare it with the online version? Let's say you have a CD with 12 tracks and the band goes live with 15 tracks, playing 3 as a bonus. Did this just make your CD less valuable? I don't see how so, since you got exactly what you paid for: 12 tracks described on the cover.

Of course there will always be games that raise budgets on KS and never ship; there will also always be simply bad games, technologically. It's a part of the creative process, just like having bad restaurants in every major or minor city. There are 2 ways to address this: (1) install a system of permissions like in Italy, where opening a new cafe in a village takes 12 months of correspondence with Rome; or (2) install a system of ratings like TripAdvisor or Yelp, which will effectively guide consumers to the better places, and let the bad places stay in the corner where they can't hurt anyone.
That's another good summary.

I forget that we're on the platform which is called Good OLD Games.

In fact, the desire for "DRM-free" could be actually a desire for "retro" or "authentic", if you use a more general terminology. There's a chain of shops in Germany called Manufaktum, which sell products produced in a traditional way. For example, a table football game made with porcelain figures of footballers and a wooden playing field. These things recapture the era and tradition of small-scale manufacturing process.

The key to their continued success? The authentic table football costs €1,500 (versus €200 for the modern plastic version). The authentic plush toys cost €40-60 apiece. So essentially you have a small community of people who appreciate certain things, and that small community is generating enough revenue for the manufacturing to happen.

If we apply this on GOG... you'll have GOG actually commissioning the development of new games under the "GOG code of values": no online requirement, LAN tools for everyone to use if the game has multiplayer, etc. Let's say GOG would invest €500K–€2M into each product. Let's say there are 50,000 active consumers on GOG. Let's say that cost of delivering the content/running platform is ~30%. So to pay back €500K, we need to generate revenues of €750K. That's €15 per consumer (Let's leave aside VAT for now). Now, considering the sales events and that people are buying on average at 1/2 price over 2-3 years of life-cycle, this would be more like the game retailing at €30, and scoring average sales value of €15. Moreover, as a bonus, you can still sell the game also on Steam, and score extra revenue there (say, double it?).

The million dollar question: why this is not happening?