I think it depends on the audience you're selling to.
There's still a portion of the non-tech savy (my parents for insurance) who when given say foo.io will go to either foo.io.com or fooio.com or shorten it to foo.com inexplicably.
If you're selling to tech companies b2b on the other hand, no need worry.
It only took a few seconds to explain to family members that .com is an extension, there were only a few in the past for com/net/org and countries but they've added a bunch more. That is usually followed by a "oh, interesting" and that's it.
There's still a portion of the non-tech savy (my parents for insurance) who when given say foo.io will go to either foo.io.com or fooio.com or shorten it to foo.com inexplicably.
If you're selling to tech companies b2b on the other hand, no need worry.