Given what happened with 4e I believe this has been in development for a while now. I certainly don't believe they announced it and started development the next day.
You're assuming it's even is in active development! Which is a hell of an assumption!
I don't think there's any reason to believe that. I strongly suspect, based on the information we have, it's actually in pre-production, the phase before active development. Software and games often spend months or even years in pre-production.
Unreal Engine 5 has only been available since April 5th. So, at most, assuming they hit the ground running, with experienced Unreal developers (which I haven't seen any evidence they have, though I obviously can't prove they don't), they've been developing since then, which is what, 3 months?
That would assume pre-production happened much earlier. But that's undermined, pretty harshly, by the messaging they've put out. Specifically, as of the CGI bullshot trailer they released a few days ago, they were still talking about the business model and how exactly the VTT will work speculatively, rather than factually.
That suggests the basic design is not finished. That suggests they're in pre-production. Which would make sense, because of the timing of everything involved. They only just bought Beyond on the 13th of April. So that actually pushes the timeline along - they couldn't realistically have started development before that, and more realistically, they'd take time to look at the Beyond database, to see what the Beyond people had achieved with their attempt at a VTT (which seems, like all Beyond projects, to have gone exactly nowhere, I admit), and so on. So probably we're into June before they've even finished looking at that and onboarding Beyond people and so on.
So I think it's most likely they haven't even started actual development. They're doing pre-production stuff and trying to work out their business model - that'll have a huuuuuuuuuuge impact on how they design the VTT.
Which makes the belief that they'll have this ready by 2024 even more wild.
In the video, they explicitely mention a release date of 2024. If people think in earnest that 2024 is "January 1st" and not "December 31st", it's a release 16 months for now and they'd be right to expect a beta testing period starting in a few month... They may be mildly disappointed.
People won't mind if it's December 31 2024, people are used to that. But the odds of it even being in a playable, non-alpha form by any point in 2024? Very low (unless they do a 2D and no-business-model version). It would be truly shocking if they managed that, given they're using the UE5 engine, and don't seem to have an experienced dev studio working on the product.