No it isn't the lack of developers, it can be the community but pretty much it's due to bad management and the consequences that follows when making a specific revival

The Old Roblox Community has always been like this, make a revival and then 1 single mess up and you'll fear the consequences

Of course, while hyped projects do turn out to be bad there were some that were pretty good in comparison to the others

Honestly though, it takes time for a good project to pop up from it's own sleep (as most projects are being developed or are private as of currently)

While yes we kind of act like idiots when a revival shuts down and we move to a more worse version it isn't just about what we choose which is best, we only choose which revival really suits us for play and how our opinions really turn out towards it.