By all means, advocate for making it easy to change the language back to the original. But this stance will decrease accessibility.
You don't, plenty of developers are getting around having to know English as there are other resources for learning.
I think it's a dangerous assumption that everyone knows English. It's especially true in the Spanish-speaking world, where I know developers who can't have a conversation in English but are good enough to be employable.
For example, take their Swedish translation of “pull request”: “Pull-förfrågning”. They had to leave “pull” untranslated, probably because it would be impossible to understand if you actually were to translate it word by word; unfortunately “pulla” is a sexual slang word in Swedish [1], so the whole translation sounds like a request for sexual assistance.
Table shows that "pull" is usually referred to as "pulla" but the suggestion is to change it to "rycka". If you do know Swedish, there is a discussion about the naming of "pull" here: https://github.com/bjorne/git-pa-svenska/issues/30
In Sweden, you can assume that pretty much everyone understands English, so if your website has an incomplete Swedish translation, might just be better to go with English one anyways.
But in Spain (outside the big cities), not that many people do understand English. In that case, it'll be better to serve a incomplete Spanish version instead of in English, as otherwise they'll be completely lost.
So as always, I'd say it really depends, and it's hard to generalize over all "international users".
I'm a native English speaker, so I don't know.
France has an obsession about its language (which is wonderful) and believes that the whole world should adapt (which is dumb in tech). You should attend some union meetings where all docs are expected to be in French "because that's the law". The reality of the world is not a concern of theirs.
Source: I am French, work in tech and see how much this illusion of "everything in French" hurts us. If you do not speak English then either learn, or work outside dev.
You wouldn't be able to have a software design session in English, but they would understand specific English words and even use them when speaking Spanish generally.
Good to know
You can switch language quite easily using the menu in the bottom center/right.
Also, in a self hosted context you can disable/enable languages in the configuration file easily.
Also, if you find the translation really bad (I think in most cases, the default translation is from MS automatic translation), you cam easily contribute to it:
-> https://crowdin.com/project/gitea
I personally contributed to the French translation a few years ago, which was really bad in Gogs at the time, specially with some over translation of technical terms such as "git commit" which was translated to "git commission" (a bit weird and laughable since "faire une commission" can be a weird formal way to say "pooping" in some contexts).
I took me a few hours to go through a few of the message strings and propose an hopefully better translation. It's quite easy to contribute to the project in this manner, far easier than contributing code.
Lastly keep in mind that gogs was created by a Chinese developer, and I'm half expecting that Chinese developers are not as fluent in English as developers from India or Europe. In this context, pushing for an internationalized service is a good call vs an English only UI.
Not translating isn't really a solution.
Wanting everything to be 100% translated is also unrealistic.
E.g. looking at the quality of Microsoft's German translations (which seem to be done by a poorly trained bot), the translation is actually counterproductive, because it's full of special terms translated into German that either would not be translated from English in a "native" German text, or where a different translation is commonly used.
My favourite is the Visual Studio translation for Link-Time Code-Generation. Which is translated as "Link-Zeitcode Generierung" which in English means "Link Timecode Generation".
In other countries like Russia or Japan I noticed, as an outside observer, more reliance on translations.
When translating a complication is the degree to which one does it. There are terms which can be translated and some where it becomes weird. In some parallel comment "pull request" was mentioned. Translating that certainly becomes weird, but translating "file" as "Datei" is well established and - when translating - expected.
I do agree that it’s not a walk in the park because it takes loads of resources to provide actual translations and one has to make i18n a feature in the code. But... come on. phpMyAdmin was doing this in 2004.
However finding the right translation level in technical context is hard. For which concepts should one translate the name and which terms should one borrow the English term? The French translate "computer" as "ordinateur", the German "Rechner"/"Rechenmaschine" however is outdated.
Now what about a git repository clone and commit? How much translation will destroy understanding?
Unfortunately that's misunderstanding that fundamentally language relies on way more context than just strings to get the same message across.
You can't just simply translate and have a good UX for other languages.
So many people seem to think that providing low quality translations is improving accessibility. It isn't. It's doing the opposite, pure english websites provide much better UX to international users.
BTW, Microsoft with their automatically translated MSDN docs is by far the worst offender in this area.