I don‘t know about Edge, but I think you are spot on about the IE4, IE5 era. At least what you write fits very well with what I remember from that time: Even outspoken Netscape proponents used IE 5 secretly.
On the other hand the article is about the UA string and isn‘t meant to be an accurate browser timeline anyway.
For example, it says:
„And the followers of Linux were much sorrowed, because they had built Konqueror, whose engine was KHTML [..]
Then cometh Opera and said, “surely we should allow our users to decide which browser we should impersonate, [..]”
If I remember correctly, Opera came before Konqueror and KHTML.
On the other hand the article is about the UA string and isn‘t meant to be an accurate browser timeline anyway.
For example, it says:
„And the followers of Linux were much sorrowed, because they had built Konqueror, whose engine was KHTML [..]
Then cometh Opera and said, “surely we should allow our users to decide which browser we should impersonate, [..]”
If I remember correctly, Opera came before Konqueror and KHTML.