Instead, consider that you chose to leverage your web development work by taking what fb has jumpstarted with a lot of their cash. You can also think of it as second-hand-investment for your thing, and you don't have to sell any part of that to get the money/talent.
And yeah sure, that second-hand-investment money might dry up at some point, but you can still continue to use what you got when you decided to go that route (it's not like your react project is going to suddenly fail, why would it), and since it's a huge project and you are not the only one to have made that choice, you can likely still count on enough third-hand-investment for it to not be any problem in the future.
All in all, I would say that if this is your most worrisome dependency you are probably in pretty good shape.
Instead, consider that you chose to leverage your web development work by taking what fb has jumpstarted with a lot of their cash. You can also think of it as second-hand-investment for your thing, and you don't have to sell any part of that to get the money/talent.
And yeah sure, that second-hand-investment money might dry up at some point, but you can still continue to use what you got when you decided to go that route (it's not like your react project is going to suddenly fail, why would it), and since it's a huge project and you are not the only one to have made that choice, you can likely still count on enough third-hand-investment for it to not be any problem in the future.
All in all, I would say that if this is your most worrisome dependency you are probably in pretty good shape.