Semantic HTML and the Semantic Web are not really related, other than both of them having "semantic" in the name.
> I see someone has sneakily added ActivityPub to the end of the list on wikipedia in 2021, retroactively giving them a success.
Why retroactively...?
The point of these standards is that they all build on top of each other. ActivityPub builds on JSON-LD which is a variant of RDF which uses the existing RDF schemas to define its attributes.
The different bits of the stack are used in many different ways. RDF datasets are really common in many different academic fields and ontology composition (which has always been a thing) has pretty much been subsumed by the semweb standards.
Semweb standards are also the most common standard in graph databases.
New W3C standards, such as ActivityPub, appear all the time and usually build on the existing semweb standards.
> I see someone has sneakily added ActivityPub to the end of the list on wikipedia in 2021, retroactively giving them a success.
Why retroactively...?
The point of these standards is that they all build on top of each other. ActivityPub builds on JSON-LD which is a variant of RDF which uses the existing RDF schemas to define its attributes.
The different bits of the stack are used in many different ways. RDF datasets are really common in many different academic fields and ontology composition (which has always been a thing) has pretty much been subsumed by the semweb standards.
Semweb standards are also the most common standard in graph databases.
New W3C standards, such as ActivityPub, appear all the time and usually build on the existing semweb standards.