It's possible to be smarter than that. I believe Chrome doesn't drop down to punycode if it sees the string is entirely within a single language so that there is no possibility of look-alike characters. It might even be checking explicitly for the presence of look-alike character pairs, since they're known ahead of time.

“People whose names break my system are weird outliers. They should have had solid, acceptable names, like 田中太郎.”

— Falsehoods Programmers Believe About Names https://www.kalzumeus.com/2010/06/17/falsehoods-programmers-...

Just look at 田中太郎. Four completely independent glyphs, equal widths, no modifiers, in left-to-right order. It is a very good way to write things. The only issue is the fourth one seem to barely have enough pixels.