We were working on ways of making it easier (such as CRDTs to reduce the amount of work developers had to do to leverage eventual consistency), but these were pretty challenging problems to solve.
One of our biggest disappointments: we had plans to add a way to enforce strong consistency leveraging (IIRC) something akin to multi-paxos, but couldn't get it to work.
that sounds like a painful session
TBH, we shipped fully working strong consistency in 2014. It just had a limited feature set, was disabled by default, and was never promoted/marketed since it didn't fit the direction the new CEO/CTO was pushing.
The engineering exodus around that time sorta killed the project though, and we never were able to do the big follow-up work to make it really shine.
(Disclaimer: Former Basho Principal Engineer, primary author of strong consistency work, lead riak_core dev from 2011-2015)
I think another 18 months would have been enough too. But it just wasn't the right environment after the hostile take-over / leadership transition.