The 2020 ARRL/TAPR Digital Communications Conference (DCC) will be held online as a virtual conference on its originally-scheduled dates of September 11-13 (details to follow). Organizers plan to hold the 2021 conference in Charlotte, North Carolina, which was to be the site of the 2020 event.
At this writing, the Friedrichshafen hamfest in Germany was still on track for late June; and the Tokyo Ham Fair was sticking to its temporary dates of October 31-November 1. The Japanese show had been previously rescheduled due to the Tokyo Olympic Games, which have themselves now been delayed until 2021.
Several amateur radio-related businesses and organizations have closed their offices as of late March, including CQ, the ARRL and AMSAT, in accordance with state restrictions on "non-essential" businesses. Ham retailers have various restrictions in place, depending on location. Some are allowing limited number of people into their stores, while others are doing mail-order and curbside pickup only. Check with your favorite dealer for specifics.
Many DXpeditions have also been postponed or cancelled. See News Bytes and the DX column in May CQ for details.