Alfresco has always been very clear that they do consider Share UI to be a product nearing its end of life, and put all their focus on building ADF / ACA / ADW as the future UI framework / standard application(s), yet are not planning to end support of Share anytime soon. One of the official statements can be viewed in this clip from the 2018 DevCon. During 2019 DevCon, then-CEO Bernadette Nixon stated Share would be supported through 2022 - I cannot find the specific point in the recorded sessions, but tweeted about it on the day of the conference, which the responsible Alfresco product manager confirmed with a slight clarification.
Of course the acquisition of Alfresco by Hyland last year may mix up any plans Alfresco might have had until then...
As @afaust has written, our development focus is still ADF/ADW/ACA but that Share is in full support and will remain so for the foreseeable future, certainly for a long as ACS 7 is officially supported.
Digital Community Manager, Alfresco Software. Problem solved? Click Accept as Solution!