As a professional technical writer, I can say that there are a couple of problems in writing international "English" documentation.
Meaning documentation that would be understood all over the world.
The first is the "US influence": US writers mostly use "Brand" names for products instead of generic product descriptions. No reader outside the US understands what they're talking about.
The "UK university/Eton/Oxford/Cambridge" writing types are even worse: using Shakespearean verbs and nouns to show their superiority make their technical articles unintelligible for everyone else.
I've worked 35+ years in this area and it hasn't improved...
I have also done technical writing and translation professionally (not for 35 years yet, though! :p ) in English and German, and genericized trademarks are something that I think everyone uses in their own language (not just native English speakers, and not just Americans). Yes, we Americans say “Kleenex” for a tissue, but the British say “Hoover” for vacuum cleaner, the French often call a ballpoint pen “un bic”, Germans say “Tipp-Ex” for correction fluid, the Swiss say “Bostitch” for a stapler, many Asian languages use “Ajinomoto” to refer to MSG, everyone except English speakers say “Maizena” for corn starch, and truly
everyone says “Aspirin” for acetylsalicylic acid. The last is a great example of how genericized trademarks are sometimes the
only word that people commonly know for an item.
That you think only Americans do this, and not other English speakers, is to me more indicative of you having learned British English originally (thus not recognizing non-American genericized trademarks as such), and not recognizing the genericized trademarks in your own language. (If anything, I feel the British actually may use more genericized trademarks than Americans, though this is based only on my impression, not any kind of data.)
Even in electronics engineering I don’t think it’s in any way justified to single out Americans: yes, we often call a phono jack an “RCA” jack, but in German you call it “Cinch”-Buchse, which is also a brand name. How about how you commonly say “WAGO-Klemme” regardless of who made it? We all say Torx even if it’s an unlicensed knockoff. (And it’s correct to call a Phillips screw by that name, since that’s a specific design that’s not the same as other cross-type screws.) The British often call for a “Megger” for insulation testing, even if they’re more likely to be using a Fluke these days.
Anyhow, I think the overall advice in this thread is good, though: avoid colloquialisms and cultural references, and keep language simple without dumbing it down. Consistency is critical.
I’ll add that, generally speaking, the things that make a text better for non-native speakers (or better for translation into other languages) also make the text better for native speakers. I’m a total advocate of straightforward writing, not the flowery, padded, obtuse BS loved by academia and legal professionals for so long...