I want Apps Script to be around for a long time.
I don't see any other alternative for myself, but I'm always hoping for new possibilities.
I've changed to using some of the Advanced Services rather than the built-in services.
If I needed to, I could transition from Advanced Services to either the REST API or an SDK for a specific language.
I've been trying to learn more about alternative possibilities through the Google Cloud Platform.
As others have mentioned, Apps Script is great for certain situations.
The solution that is best for you depends upon what your needs are.
Apps Script is the best, number one, awesome, and super duper greatest thing out there for low/no cost solutions, individuals, small organizations,
low traffic, "citizen developers"; anything where the budget is a concern; you need low cost entry to services; you don't have an amount of traffic
that will crash your app; you don't need to "scale up"; and nobody is going to die if a bug makes your app unusable.
If you are a doctor's office who needs to know if your patient is dying, then don't use Apps Script.
It can even be good for professional developers who charge for add-ons.
But, there are limitations, which isn't surprising for a product that is technically unsupported, you can't buy support for, and is free.
There are probably reasons why Apps Script is technically not supported.
Apps Script is "sort of supported" by the Issue Tracker, but other than that, Apps Script is not really supported.
It's probably part of the business model and the legal environment.
As soon as a company requires payment for something, there is an expectation of guarantees and a certain level of quality.
You can't call someone at Google and tell them that the Apps Script code that your business relies on failed,
and caused X amount of damages to your company, and you want your money back.
This isn't just an issue with Apps Script, if I had to buy insurance to protect me against damages to my users from a bug in my app,
then I'd need to charge everyone a million dollars a year (exaggerating a little) to cover possible liability.
That won't work when people expect something for nothing.
Even though I may complain bitterly about the failings of Apps Script at times,
I'm not sure where else I'd go. I'm kinda stuck here.