Email in a large part is just a tool for communication(and mostly low priority at that). Where I work, we have backups: Teams( same) provider, Cellphone ( different provider ) , Landline( different provider)

We had a situation recently where cellphones were down, we switched to landline.

You don't need a 1 to 1 mode backup for everything, just a failover plan.

Unless your company is infrastructure or medical, I doubt they have a backup/failover for loss of power. Or water.