unfortunately my thoughts on tone indicators are somewhat nuanced. fortunately, this is tumblr not twitter, so I can just write out my full thoughts in one post and be as verbose about it as feels necessary.
speaking as an autistic person (and I know there are other autistic people who don't hold this same view, this is just my perspective), I think as an accessibility tool, the extended set tone indicators in current popular use is fundamentally misguided.
the oldest ones, /s for sarcasm and /j for jokes, make sense. their notation isn't the most intuitive thing ("does /s mean sarcastic or serious?") but it's not too difficult to explain what they mean. I've had to spend my whole life learning by brute force what different tones of voice mean and what they change about how I'm supposed to interpret something, so I already know what "read this in a sarcastic voice" and "read this as a joke" are supposed to mean. my existing skills can be translated into the new form without too much effort.
the same thing applies to emoji and emoticons. I know what facial expressions mean, because I had to learn what they mean. figuring out if :) is sincere or not from context is a skill I've already needed to develop. it doesn't come naturally for me, but it's something I already at least somewhat know how to do.
most of the tone indicators in current use uh. don't work like this.
tone indicators like /ref or /nbh don't correspond to specific tones of voice. I don't have a "I'm making a reference" voice or a "I'm not talking about a person who's here" voice that I can picture the sentence being read in. these do not indicate tones, they're purely disambiguators. they clarify what something means without necessarily changing how it would be read out loud.
and on paper, that's fine, right? like, it's theoretically a good thing to take an otherwise ambiguous statement and add something to it that clarifies what you meant by it. the problem is that these non-tone tone indicators are not even remotely self-explanatory. it's up to me, the person who is being clarified to, to know what all these acronyms are supposed to mean, and how they change the way I'm supposed to interpret what something means.
it's, quite literally, a newly-invented second set of social cues that I'm expected to learn separately from the set that I've already spent my whole life figuring out, and it works completely differently.
sure, these rules are (in principle) less arbitrary than the rules of facial expressions and tones of voice and how long you're supposed to wait before it's your turn to speak, but they're also fully artificial and recently invented, which means they're currently in a constant state of flux. tone indicators go in and out of fashion all the time, and the "comprehensive lists" are never helpful.
in theory, I appreciate the idea of people going out of their way to clarify what they mean by potentially ambiguous things they post online. if it worked, that would be a really nice thing to do.
however, sometimes I imagine what the internet would be like without them. what if instead of using /s, the expectation was that if you're sarcastic online there's no guarantee that strangers reading your post will know what you meant? what if instead of inventing more and more acronyms to cover every possible potentially confusing situation, we just... expected one another to speak less ambiguously in the first place?
so, I on paper like the idea of tone indicators. I think it's good that some people are trying to be considerate by being extra clear about what they mean by things. but if tone indicators didn't exist, and people who wanted to be considerate in this way instead just made a point of phrasing things more clearly to begin with, I think that would be vastly preferable to even the most well-implemented tone indicator system.
also /pos sucks because there's something deeply and profoundly wrong for an abbreviation that means "I don't mean this as an insult, don't worry" to be spelled the same way as an acronym that's an insult