I understand that they/you are probably being flooded by a lot of AI slop apps or other excuses, but submitting an app 3 weeks ago and it being stuck in Waiting for Review (not first app live on app store either) is beyond a joke. Lodge a support request (not expedited review request) and to get back a generic you will be notified when it changes to In review is not the sort of support help you would expect either.
This sort of delay impacts businesses (time and money) and needs to be fixed by either putting more reviewers on - OR better still move more towards the Automated review process Google uses. meantime it still sits there in waiting for review.