If I recall correctly, both IZF and CZF include intuitionist versions of the Axiom of Infinity, suggesting broad acceptance, not rejection, of actual infinity.
I agree with you jsfisher, we should not talk about acceptance or rejection of Actual Infinity, but about the understanding of the notion of Actual Infinity.
The first step in order to understand this notion is to ask: "What is Actual Infinity?"
My answer is:
Actual Infinity is the existence that is logically always true (tautological existence).
IZF, CZF or ZF are axiomatic frameworks about sets, so in order to understand Actual Infinity in therms of sets, we first have to understand what is a set in terms of existence, where tautological existence and non-tautological existence are
(a) and
(b), as follows:
a) The discovered platonic (and therefore objective) level of existence, where this level of existence is logically a tautology (existence is always true) (this notion is symbolized by the outer "{" and "}" of any given set, whether it is empty or non-empty).
b) The invented non-platonic (and therefore subjective) level of existence, where this level of existence is logically not a tautology (existence is not always true) (this notion is defined between the outer "{" and "}" of any given set, and its non-tautological existence is symbolized (in the case of non-empty set) or not symbolized (in the case of the empty set)).
In other words, as long as IZF, CZF or ZF axioms are used in order to understand Actual Infinity in terms of
(b), no understanding of Actual Infinity is established.
Here is, for example, ZF Axiom Of Infinity:
"There exists a set X
(this is (a) part of the axiom) such that
(this is (b) part of the axiom) {} is a member of X and, whenever a set y is a member of X, then S

is also a member of X."
By this axiom, X has two levels of infinity, where
(a) is the actual level and
(b) is the non-actual level.
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A request like "Please show me a member of set X that is missing from X"
(where the aim of this request is to support the notion of completeness (and therefore Actual Infinity) at
the non-platonic level of existence of members) is irrelevant if one
understands the different levels of existence of set X, by using Philosophy
(as meta-view of Mathematics) and Mathematics (the non-platonic level of
existence of the members of set X is inaccessible to the platonic level of
existence of set X).