I fully agree, Ubiquitous Language is the key part of DDD. As long developers and business people understand processes and speak the same language you can achieve DDD using any patterns/languages/technologies.

In DDD what I find the most challenging are changes and context: e.g. in typical sass application marketing team speaks about customer that comes from PCP, but from sales perspective customer is the only company setup through CRM system. Same word but often processes are completely different (post-pay, pre-pay etc).

Sadly, I never work in a team that implemented fully DDD - mostly because it was too hard to engage all departments to think about processes - technology behind that was the easy part.