The term "real-time" means that you can guarantee certain timing constraints. It can only work on a substrate (OS) that supports real-time processing. So I am sure that "real-time" is not what this package is offering.
Sorry to tell you this but the term now has a different meaning within the web development community.
If that bothers you then regain your composure by remembering that 'computer' once referred the operators of calculating machines - not the machines themselves:
The parallel to "computers" does not fit in this case, because that change came to the entire world at the same time, via the same mechanism: computer -> electronic computer -> computer (when human computers became obsolete).
In this case, the existing meaning of "real time" is not obsolete, so the analogy does not work.
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Next, just because language inexorably changes over decades, generations, and centuries, does not mean that a subculture deciding to use an existing word in a different way is "The language changing."
It's just a subculture deciding to use a word in a different way. When they go forth and use that word outside of their niche, and there is confusion because they mean one thing and the rest of the world means another, the subculture does not get to shrug and say, "language changes."
When you use words, it is your responsibility to know your audience and use the words your audience understands, in the way that they understand it.
And so it is with technical terms that have established meanings in the computer science and programming community. By all means redefine what "class" or "type" or "realtime" means. Use your definitions within your subculture with abandon. But be aware that when straying outside of your community, it is your responsibility to use terms that your audience understands, not your audience's responsibility to presume that all bets are off, and any word might mean anything.
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Finally, I question the tone of "sorry." Perhaps you didn't mean it that way, but it has an air of the arrogance of a pop culture programmer. "We're inventing new stuff here, no time for your old ideas, daddy."
It would be helpful if instead of snark, you responded with an actual explanation.
Especially since a quick search of "real time javascript framework" doesn't return one. The most relevant result suggests that a chat application or dashboard is "real time". When it's really just two-way communication (sockets et all).
In this context, it doesn't appear to mean anything at all AFAICT (aside from marketing) as any framework with some minimal helpers supporting sockets could use the label. Or not... since despite your response, it's possible I've misunderstood since it's not actually a "web development community" bit of language AFAICT. Having been a member over a decade.
It irks me too, but the term has been adopted in recent months, I think, by the javascript community. It is usually used to mean something akin to reactive.
My guess is that they are pulling that from Socket.IO's use of the same "real time" term. Which I suppose is to denote that it's not ajax polling (though I understand that Socket.IO does poll in some situations...)
If that bothers you then regain your composure by remembering that 'computer' once referred the operators of calculating machines - not the machines themselves:
https://en.wikipedia.org/wiki/Computer#Etymology
Language changes.