The Eurocentric bias we don't usually talk about
Now, eurocentrism in auxlangs like Esperanto has been debated a lot. This is not what I am going to talk about today. I haven't found writings about the specific point I will talk about so that's why I wanted to bring it up.
Nearly all auxlangs have romance-germanic logic and structure almost word by word. Replacing vocabulary and some grammatical features is not enough to avoid Eurocentric bias.
Grammar is how you structure thoughts, how you reference the language's logic, and how you build and re-build meanings. One must contend with a languages' backbone in order to examine bias. And when you step outside of the romance-germanic-auxlang sphere, you see that a lot of what we take for granted in auxlang logic, coupled with our deep intuitions of what is "simple" or "easy", is deeply Eurocentric. When you look at languages like Japanese, Arabic, Yucatec Maya, and Turkish, you can see this much more clearly. And then you realize that actually, a vast number of languages worldwide are deeply distinct from romance-germanic. They operate in totally different and fascinating logic and structures.
For example, take the features of what I would call "Standard Auxlang". SVO order, which in reality is not even just SVO order (which is common) but rather almost everything in romance-germanic order. Then you have explicit pronouns; European-style subordination; topic and focus as an afterthought; large verb systems primarily tense and secondary aspect; lots of "be" and "it"; gerund everywhere; the standard list of correlatives; romance-germanic suffixes, prefixes and word derivation; almost no information structure like comment or evidentiality. Notice that there is nothing inherently European about any of these in isolation. The point is, when you use these in aggregate, you end up with romance-germanic logic and sentence structure almost word by word.
There are so many unexamined assumptions about what makes a language easy, simple, or universal that we may not even be able to picture how these little things could be different. And yet they are, in a rich linguistic landscape that we have in natural languages worldwide. The community barely has space for languages outside of this Euro sphere to contribute much more than just vocabulary, they are not allowed into the very own foundations of auxlangs.
I am not talking here about auxlangs that are based on European languages and explicitly so. They tend to be clear about what their tendencies are. It's almost worse to still have a largely romance-germanic auxlang landscape while saying otherwise because biases are left unexamined. Whether the community is willing to examine its assumptions of what is easy, familiar, intuitive and non-eurocentric is worth asking.
Now, there are a few auxlangs that are significantly different from romance-germanic-auxlang structure and logic. They may be organized with topic-comment structures, aspect-first verb systems, role markers, zero pronouns, and other things that feel unfamiliar to Euro speakers. But these auxlangs are not numerous, and they may not benefit from the same perceived easiness and familiarity as Standard Auxlang.