[pjmlp]

Lowering case is even better, because a Swiss user would expect the two-character sequence “SS“ to be converted into “ss“ and not “ß“.

And thus we add country specific locale to the party.

[account42]

Not just a Swiss user as there are many German words that use ss and not ß. And having an ss where there should be an ß will be a lot less disruptive as the inverse because people are used to ASCII limitations.