Development for Nextcloud is very active, and it is very hard to evaluate the current status, particularly with respect to new features such as client-side encryption.
Deciding whether to adopt the feature depends on understanding whether it is mature enough to be safe and stable. I have had difficulty finding a consensus opinion on this subject. My understanding is that E2E is included in recent releases, but how thoroughly has it been tested to date? Does it yet meet its promise to avoid data corruption while at the same time providing a high level of security against attack? Can someone better informed about recent developments offer a summary of the current status?
(Note, I am aware of a serious problem on the desktop client, affecting any site for which E2E is enabled administratively, regardless of whether data any folders are marked for encryption. At minimum, this problem would need to be resolved before adoption is feasible.)
Thanks for the help.