From my experience aquacomputer's after sale support is very good.Definitely not the best way to market a product... but let me say, living in Germany, that's not a priority here.
You take what is the offer; not happy? Get lost. Go somewhere else, don't waste my time.
A cordial welcoming is something very rare in most of Germany.
This kind of behavior for software support for an hardware device is legit.
If there's a breaking bug and you can't use it at all when you bought it, that's covered by warranty.
It's a Dead On Arrival. But if it happens after your return period, means litigation.
Maybe you start using it after 6 months and a new Windows version is not compatible with the software you activated earlier?
That's your problem; you need to buy the upgrade.
It's not helping sales and not consumer friendly. But that's it.
On the other hand, their communications has room for improvement, but as you stated, that may reflect a cultural difference in expectations.
Your point "Maybe you start using it after 6 months and a new Windows version is not compatible with the software you activated earlier?" is precisely what the licensing scheme attempts to address. The product you purchased worked when you installed it, with the system you install it in. If you modify the environment with newly developed options, you cannot expect an older product to work without additional development.