I just filled another form on an English website that didn't have name set for the HTML "submit" button. The browser filled in "Prześlij", which is "Send" in Polish. Given how many pairs of website and browser languages there are, I wonder if this automatic naming of controls can cause problems. Does this featuer of automatic button naming can lead to actual errors in some cases when the user assumes that the name of the action is spelled out in the website's language, but it's actually in the browser's one and the same word means two different things?
"Submit" in English is the most benign wording for literally "send". I'd imagine it's been named consistently in all localization formats. I would say browser localization is done by native speakers of the given language, and have been vetted by browser users. So the chances of the localization using ambiguous wording is rather low.
Another thing is, web forms has been around since late 1900s. If there's a single primary button on a page. It should be pretty obvious that you'll need to press it for the page to do something.
If there's more than 1 button and the developer is too lazy to label them, then I think you have bigger problems then the browser automatically naming them "submit".