All of this advice is very familiar. As a manager in the pandemic I was enrolled in countless mental health training seminars. But as someone who took a mental health leave due to burnout and had two direct reports require time off during the pandemic for the same reason, I can honestly say the best thing managers and companies can do is let staff take time off when they're feeling overwhelmed. Make it known the organization will adjust and their job is secure when they return. Burnout, anxiety and depression is not something you can "manage". People need the time and space to feel their feelings and it shouldn't come at the expense of their job security.