Budweiser got the first big Super Bowl commercial victory of 2021 when Anheuser-Busch announced they would not have a commercial in The Big Game. It is the first time in 37 years there will be no Bud on TV during the Super Bowl and it has been far more effective for brand awareness than any actual commercial would have been. Why, just look at this paragraph. There are multiple instances of brand mentions.
"Budweiser will give the money it might have spent on running a Super Bowl commercial to the Ad Council, an industry coalition that produces and places public-service announcements, to help raise awareness of the benefits of getting the coronavirus vaccine."
This is apparently a recent decision. Earlier this month Ad Age reported that there would be a 60-second Budweiser ad. Perhaps there was some feedback after that was announced since the beer giant just laid off 400 people in October. Whatever their motivation, the news that they wouldn't air an ad has been met with a lot of coverage. As Josh Noel of the Chicago Tribune pointed out, AB InBev will still be all over the Super Bowl.
Other companies, including Coke and Pepsi, have also opted out of in-game ads. Of course, Pepsi is still sponsoring the halftime show and running ads for Mountain Dew and Frito Lay products. It's all about how you allocate your advertising budget. Budweiser just appears to have found the best use.