In every base, a 1 in the second spot corresponds to the name of the base.

even when written out non base ten systems, are still possible to be non base ten.

It's only base ten when you convert from one base system to another. We are merely referencing between two base systems when we say that 4 bits is "16" because there are 16 possible options there. 16 is just our conceptualized version and conversion of that base system, in ours. You can read binary as if it's just powers of 2, it's incredibly trivial.

octal and hex are the best example of this, because octal skips numbers while counting. Hex introduces letters. Neither of which fly even remotely sanely through base ten. Unless you're converting.

"ten" is a fixed amount in base 10. A base 4 user may have an entirely different naming system for numbers above 3, so "ten" (which is written as 22 in base 4) could be twenty two, twoty two, dbgluqboq, or Janet. But similarly to how we don't have a single syllable, dedicated number name for decimal 22 (as in, it's composed of the number names 'twenty' and 'two'), they may not have a single syllable, dedicated number name for decimal 10 (which is '22' in base 4).

What about Roman numerals?

we'd only be able to represent bases for numbers with one digit though because what does base 15+1 mean? the 15 could be in any base higher than 5. the clearest way would probably be to just represent it with lines or something "base ||||||||||"

And those who didn’t expect the joke to be in base 3