Concrete examples
L’Oréal → loreal.com
Côte d’Or → cotedor.com
François d’Assise → francoisdassise.org
In all these cases, accents and apostrophes are removed, yet the text remains intuitively readable.
So yes, writing "lempereur.com" is a technical simplification, not an error. It is understood by everyone as "l’empereur" (the emperor)—exactly as you noted.