We did weigh the options for/against but went with Firebase because they got acquired by Google and the Founders (and Google) made public promises not to shut it down.
Again, we don't rely entirely on Firebase. There is always another database (like AWS Dynamodb or Google Cloud Datastore) in the picture ... but again all hosted in the cloud ... not much servers to manage for my team.
If Google and AWS shut down ... thats when the fit shits the fan :)