Socialise on the company clock
Consider keeping work socialising and team building to work hours. More than ever, people should turn off the computer at the end of the day to clear their heads. You may get more support if you knock off earlier, have your work fun, and then people can turn their attention to what they need to fill their cups right now once the work day is over, or they can tend to others who need their attention.
Think outside the bottle
Raising morale can be done in ways other than staring at a screen with a glass of wine in hand and "touch up my appearance" set to medium - high. Ideas like online bingo, mahjong or an online cooking class all build morale and minimise awkward barriers to participation.
Even social Zooms need a leader
You know how well meetings work when someone leads them? That's the case when a group gathers online too, especially if it's colleagues and not friends. If you have a large workforce keep online gatherings to departments or small groups. The aforementioned activities work well and having someone in charge to keep it moving and flowing helps avoid awkward pauses and everyone then talking over each other.
Stick to the time limit
In a truly altruistic show, Zoom did away with their 40-minute limit but if you are planning a work gathering, set a time limit. It's only fair and means no one has to cut into Deborah from logistics' passionate monologue about her sourdough starter enhancing her latest banana bread to excuse themselves.
Above all, be mindful that people are spending all day online, then Zooming grandparents and family members they can't see, checking up on relatives and friends. The amount of time we are in face-to-face calls can be overwhelming. People may not want to participate in drinks with the team but that doesn't mean they don't like their job or their colleagues. It may mean they simply don't have the bandwidth, and that applies to introverts and extroverts alike.