I can’t speak for concrete CMS as a company, but for me personally I think concrete CMS is here to stay. WordPress offers something for some people. It’s very low-key. A lot of plugins are needed to run any type of website, whereas concrete seems to have constantly added key add-ons into the core of its system and therefore as as things have progressed there are less and less need for add-ons.
I’ve been building sites for 14 years on concrete and I’d say at the moment it’s the best it’s ever been.
Yes, maybe there are parts of the custom development areas that are not for people with very little experience, but in terms of a development system and in terms of being able to spin up quick sites, it’s excellent.
I would ask those agencies in Germany that you’re talking to. What systems do they use? Do they use WordPress? And if they do then it’s obvious why they’re recommending to go with WordPress and not Concrete CMS.
Only real concern would be what happens in 20 years when Franz or Andrew want to retire, but by then I doubt we will even have websites and who knows what technologies will be around.