This is naive at best

Here's a better analogy, in the 70s "nobody planned" for names with 's in then. SQL injections, separators, "not in the alphabet", whatever. In the US. Where a lot of people with 's in their names live... Or double-barrelled names.

It's a much simpler problem and still tripped a lot of people

And then you have to support a user with a "funny name" or a business with "weird characters", or you expand your startup to Canada/Mexico and lo and behold...

Yea, I cringe when I hear the phrase "special characters." They're only special because you, the developer, decided to treat them as special, and that's almost surely going to come back to haunt you at some point in the form of a bug.