Anosmia is the loss of sense or smell from a head injury, infection, or blockage of the nose. It can be partial which is called hyposmia or total which is called anosmia. Without a sense of taste food will become bland and it would be hard to tell foods apart. This causes loss of interest in food which in extreme cases will led to weight loss, nutrition problems and even depression. People also have a unique smell like Karl Wuensch explains, which is what he misses most, not being able to smell his friends and family.
I think most of us experienced COVID-19 and had our taste buds what felt like ripped out from us but I remember when I have COVID a few months ago I had lost my taste and it effected me greatly. I love to cook so not be able to taste any food was the biggest blow. I had trouble eating because eating food truly is boring if you cant taste anything, so I found it hard to just have the will power to force myself to eat. I only was sick and had COVID for a few days but I didn't get my taste back until 2 weeks later and during all of this I was reading stories about how people lost taste permanently after COVID and it made my anxiety sky rocket. Luckily my taste came back and I haven't had any problems since but I will no longer take any of my senses for granted.