FWIW, Avast misses a LOT of viruses (not that’s related to this topic, just reminded me).
I usually receive 2 to 3 fake postcards a day and avast usually detects only about 50% of them.
I think that response to new viruses should be faster. I keep those files and find that avast
only detects them several days, sometimes weeks after I received them.

Just yestarday I had to clean PC infected with one of those “postcard” viruses and avast didn’t detect absolutely anything.