If you have a disability, then the right to work remotely is covered as an accommodation under the Americans with Disabilities Act (ADA). Otherwise it really depends on the employer and manager.

No. People saying this most likely have others reasons to make you feel this way. (they want to and can't or they don't want and also don't want others too etc.) Remember : people are petty and until they give a reasoning with facts it's all just imposed culture.

Ah, good point, you reminded me of the classic distinctions of - “I’m ok, you’re ok” v. “I’m ok, you aren’t” v “you’re ok, I’m not” v “you’re not ok and neither am I”

Depends on the job, the reason why you can't meet and other context. Currently, I wouldn't say it's disrespectful since it's pretty normally accepted for jobs that don't REQUIRE a physical presence. But if it's just a matter of not wanting to meet someone just because, then yes, it might be disrespectful.

To what extent should social anxiety, social awkwardness, and the associated inefficiency due to extra sociocognitive demands be accommodated then?

For example, if it were hugely distracting and performance impacting to have normal office activities occur simultaneously with a regular meeting, should being able to call in be considered reasonable? And for contrast, if it were annoying to have regular office activities take place during periods of work that require concentration, how much annoyance should be considered reasonable and when would it be unreasonable to work remote most days?

Where is the line between discomfort and disease?

As long as you discussed working remotely with your managers or it's part of the job, you have nothing to worry about.

You don't really provide much detail on your situation, so I'm assuming you're overthinking things.

Disrespectful of whom? Have you asked why they think it’s disrespectful?

Disrespectful of the leadership team and of the establishment and/or workers, in general. The general idea is that everyone should be in the office out of respect to meet face to face but I presume also in fairness through sameness.

Depends on the country and culture. Where are you?

United States, Midwest