Britannica doesn't contain outright hoaxes and nonsense. Examples:
https://www.theregister.com/2017/01/16/wikipedia_16_birthday... https://wikipediocracy.com/2022/08/11/wikipedias-credibility...
But Britannica can never be as up to date as Wikipedia:
https://www.inputmag.com/culture/queen-elizabeth-ii-death-wi...
Nor can it cover as many topics as Wikipedia.
Wikipedia's quality also depends on the topic area. Hard science and computing tend to be covered more adeptly than philosophy for example.
And article quality simply varies much more in Wikipedia. It ranges from some of the finest writing anywhere, rivalling anything in Britannica and surpassing it in up-to-dateness, to complete rubbish and intentionally falsified content.