Φ - on the grounds of their philosophical training, some people are expert philosophical intuiters.
What are the consequences of Φ? The first thing it manages to do is to undermine the results of the existing studies that claim to derive some kind of philosophical raw data from the intuitions of the folk because the folk are just the wrong people to ask about these things. As such, Φ helps meet the current version/state of the restrictionist challenge. However, establishing Φ doesn't necessarily help fend off restrictionism, in fact, it opens up the possibility of a stronger challenge.
To see how this might be, consider the possibility that two philosophers have conflicting intuitions about some thought experiment / application of a concept / whatever. Note that nothing about Φ rules these kinds of conflicts, all Φ serves to establish is that philosophers' intuitions should be considered as the "proper" source of intuitions about philosophical matters.
There are a number of possible responses to this situation.
Our first would be to reject these conflicting intuitions straight out - doing this is actually just to reassert the restrictionist's challenge, only focused on a narrower domain.
Our second response could be to assert an updated version of the expertise defence, let's call this
Φ* - on the grounds of specific kinds of philosophical training, a subset of philosophers are expert intuiters.
Even if we grant Φ* though we have a problem - this is actually identifying which kinds of training lead to expert intuitions. The answer to this question will be at least partly empirical - we can't hope to come to any useful conclusions about the nature of the training required to support Φ* without actually going out into the field (I've also ignored the fact that in order to even establish a claim as strong as Φ* we would need some kind of empirical evidence to back it up).
Does defending intuitions against restrictionism require more Experimental work?
For more on this check out Weiberg et al's Are philosophers expert intuiters?