I hate email for internal work within a company. Some seem stuck on each employee having their own Outlook and reading and responding to new mails asap. For me, I'm better when I bulk reading mails once or twice a day and tell my boss and most close colleagues they can always reach me fast with a Direct Message on Teams and/or SMS.
It's ok for me to use email to deal with external work (clients, subcontractors etc), but I suppose my inbox has not yet reached the scale where it's an overload. Whenever that happens, I would certainly look to get a Virtual Assistant...