It depends on what you want virtual programs to accomplish.
In my opinion, one of the most important reasons to run these events is so the organizers can get a sense of who are the people you can support best and how to support them.
If you are already have a process in place for meeting people one and one, and you feel these are enough to give you a sense of the people in your group, you might not need your own intro program.
Also, I am not completely informed, but my impression is that the virtual programs have a low bar for admitting new facilitators (I think they might invite anyone who has completed an in depth intro fellowship? And I don´t think there are any mechanisms yet like paired facilitating to give feedback to the facilitators). So quality assurance is more of an issue - you can get a great facilitator and cohort or a mediocre experience based on luck. A local version has more control over who facilitates and the experience, if this is something you want to invest into.
Lastly, a local program can help create ties between geographically proximate members, which can lead to them meeting in person and have more interactions.
These are all pro tanto reasons. In my opinion the first one is most crucial - if you already have a process in place to meet people and get a sense of them that is probably good enough, and you can instead focusing on supporting each individual after the intro program, helping them progress in their careers, etc.
This isn't exactly the answer you wanted and is sort of ruthless:
One guess (which is very likely to be off because of lack of context) is that the person(s) who told you to run a fellowship, told you to do this as a way of resolving a problem of not getting funding, and assumed that you >80% resolved to continue.
This is because a fellowship would allow funders to observe inputs and outputs better and know the potential organizer better.
So I'm saying, maybe they viewed successful execution of a fellowship as a potential signal. For example, an organizer could express certain kinds of skill or connections (that is unknowable because the people making decisions are far away). At the same time, the absence of this success, or some other lack of promise for a fellowship (which most of the time doesn't mean a lack of ability or that someone is a "bad EA"), would prevent a potential organizer from using this signal to show ability. So a fellowship is a filter.
So, I'm basically saying the "fellowship answer" might have been an answer to a specific situation of someone not getting funding, and giving them a potential path to continue.
This answer you are reading might be beneficial, because it points out this advice might be very different than an "instruction" or "robustly good advice with guaranteed reward".