well sometimes if you don't know the person that well or if it's a loaded issue they're talking about, you just have to come out and say "I can't tell if you're being sarcastic"
.... He was implying that you may very likely have no idea that you're missing implicit statements and sarcasm, because you're, well, missing it.
The main meaning is still there and most of the time, nothing happens if you miss the implicit or sarcastic meaning, so it's very likely you'll never notice you missed it.
You actually have no real way of knowing if you are good or bad at picking up implicit/sarcastic meanings, because you would have to check each and every statement and depend on whoever you're checking with to be truthful and/or good at picking up thesr statements as well. If you don't do that and just go from your own experience, it's actually impossible for you to tell how good you are.
It's kind of funny that I have to explain this because this is a perfect example of you missing the implicit meaning, right within a discussion of the topic.
It's almost like autism is a spectrum and it can go from hardly noticeable to so severe that you can't survive without constant supervision and assistance.
It really depends on the way someone's autism effects their social skills. Not everyone has the capacity to learn these skills, Autism does create a skill cap for many people.
It's also a question of involved effort. I was in a form of ABA therapy as a kid and I was capable of learning to identify sarcasm and read social cues, so I did.
But it doesn't come naturally to me, it requires a level of concentration and conscious processing that I don't hear non-autistic people discussing. It causes headaches and migraines and after a few days of work, using these skills every minute of the day, I'm exhausted and struggle with basic tasks at home. I don't have these same issues with exhaustion or conscious processing when I'm with other autistic people (I work in disability programming, I coordinate/admin 3 days a week with mostly neurotypical people, and run programs 1 day a week with mostly neurodivergent people, and there's a big difference on how much "effort" it takes to understand people in those two environments)
Not saying it's not worth learning. If you can learn these skills they are incredibly important and at the bare minimum they will keep you safe.
But as a society we need to accept that for a small subset of people with disabilities, these skills are unachievable, and reasonable accommodations will still need to be made, and for a slightly larger subset, accommodations may still need to be made on occasion because while someone may have these skills, they might not have the cognitive capacity to employ these skills 100% of the time.
I think the reason the idea of a "skill cap" feels instantly incorrect is because there is obviously no point at which any human "stops learning". There will always be more to learn an more that someone (autistic or not) can learn.
The skill cap applies to specific metrics of measuring skill gain.
A large number of people with "level 3" autism who are non verbal will never learn to communicate verbally as fluently as non-autistic verbal people, even with decades of supportive education. But that doesn't necessarily mean they have a "communication skill gap", there's a lot of communication skills that can and will be developed with the right support. But expecting someone in that situation to "try harder" and "learn to talk" is unrealistic, when the more achievable goal should be "learn to effectively communicate".