OWL beginner question: Difference between rdfs:range and Restriction with owl:allValuesFrom

Question

as a beginner in OWL I find the difference of rdfs:range and Restrictions with owl:allValuesFrom a bit hard to grasp.

In "Semantic Web for the Working Ontologist" (2nd Edition) chapter 11, page 228f. a questionnaire is modeled somewhat like so:

q:Answer a owl:Class .
q:Question a owl:Class .

q:optionOf a owl:ObjectProperty ;
    rdfs:domain q:Answer ;
    rdfs:range q:Question ;
    owl:inverseOf q:hasOption .
    
q:hasSelectedOption a owl:ObjectProperty ;
    rdfs:subPropertyOf q:hasOption ;
    rdfs:range q:SelectedAnswer.

q:AnsweredQuestion owl:equivalentClass
    [a owl:Restriction
    owl:onProperty q:hasSelectedOption
    owl:someValuesFrom q:Answer] .

q:SelectedAnswer a owl:Class ;
    rdfs:subClassOf q:Answer ;
    rdfs:subclassOf
    [a owl:Restriction ;
    owl:onProperty q:enablesCandidate ;
    owl:allValuesFrom q:EnabledQuestion ] .

q:EnabledQuestion a owl:Class .

q:enablesCandidate a owl:ObjectProperty ;
    rdfs:domain q:Answer ;
    rdfs:range q:Question .

Now the basic idea is that if an answer is selected, a new triple along q:hasSelectedOption is added to the triple store; this allows the inference that the selected answer is a q:SelectedAnswer (via rdfs:range).

Since members of q:SelectedAnswer are also members of the asserted Restriction (subClassOf), it can also be inferred that any ?object along q:enablesCandidate is of type q:EnabledQuestion ('universal inference').

With 'universal inference' I mean, that given

[a owl:Restriction ;
owl:onProperty P ;
owl:allValuesFrom C] .

it is entailed that for any individual that is a member of an owl:allValuesFrom restriction, any object asserted along predicate P must of type C.

I think somewhere in the Pizza tutorial it says that domain/range are for inferencing, whereas axioms are for 'data integrity constraints' (?), but isn't the the subClassOf-allValuesFrom-construct in q:SelectedAnswer also used for inferencing here?

And why not just assert q:enablesCandidate rdfs:range q:EnabledQuestion?

Edit:

Sorry, I think this duplicates owl:allValuesFrom and rdfs:range difference.