Solid line = floor (spellings that unambiguously belong to the group). Shaded band up to the dashed edge = ceiling (the most it could reach if every ambiguous spelling counted here).
Dior has held a fairly steady level of use. All-time it's been given to 7,398 U.S. babies, the 1,062nd most common name by sound today, peaking at 874 in 2020, with 315 in 2025.
Dior has no common alternate spellings by sound.