Not sure if you read the article but it mentions the dolls had preeminent vulvas and sexual attributes. I think that excludes the children usage supposition.
The symbolic or humorous interpretation is much more plausible.
The article also mentions a child's fingerprint surviving in a clay figurine. This comment section is pretty wild; the article is pretty clear that there is a lack of consensus and multiple competing theories, yet so many comments seem to pick a single theory and run with that in exclusion of others.
Given that these figurines were being produced for over 10k years with a global distribution, I'm gonna go out on a limb and suggest that multiple mutually exclusive interpretations could have been true in different places and times.
And, hell, Barbie. In the last 100 years, we have observed a doll in the form of an adult woman go from being successfully marketed to adult men, to being successfully marketed to young girls. Why would we assume these Venus figurines had a single purpose?
The fact that the body parts that identified the statues as females were emphasized is likely to have been much less erotic at a time when nudity was frequent and unlikely to be hidden from the others.
Emphasizing the fertility in the statues is a reason to believe that they could have been intended for use in some rituals or as good-luck charms, but it certainly would not have been a reason to censor their use by children who would have been habitually exposed to nudity, unlike today.
