Why is the Data Roaming option missing from iPhone settings?

I am travelling internationally, and charges for Internet data are about $15 per megabyte. My provider doesn’t offer a roaming package for that. I plan to add a second local SIM using eSIM. I want to be sure Data Roaming is off, even if Cellular Data is on.

According to this Apple help page: https://support.apple.com/en-us/HT201643 in order to turn off Data Roaming, I should: “Open Settings and tap Cellular, or Cellular Data, or Mobile Data. Turn off Cellular Data, then tap Cellular Data Options and turn off Data Roaming.”

I did the above, as far as turning off Cellular Data. However, when I tap Cellular Data Options, there is no option for Data Roaming. There is only Low Data Mode. Why is it missing, and how can I assure that Data Roaming is off?

I understand that turning off Cellular Data should stop any data roaming charges. However, I don’t want to make an expensive mistake, in case I accidentally turn on Cellular Data. I want to be sure that Data Roaming is off, even if Cellular Data is on. I don’t want to experiment with turning on Cellular Data to see whether an option for Data Roaming appears.