Time is our most limited resource. We are constantly working at full capacity on all sorts of things, including exciting and essential projects like the new C3 runtime, which nobody can develop apart from us.
The SDK exists because we don't have time to implement all the features everyone wants. In acknowledgement of this, we allow third-party developers to come up with addons independently of us, so some ideas that we simply do not have the resources to implement, can be implemented by others.
For this reason it's out of the question to expect us to do any sort of maintenance on third-party addons. To start with we don't have the time anyway, but on top of that, it's unfamiliar code often written in a radically different style to what we'd use, and being dragged in to maintaining third-party code defeats the whole reason the SDK exists, which is to allow development without our involvement.
Third party developers can, and do, disappear at any time, for any reason. This has happened before, and will happen again. When you choose to use a third-party addon, you are entrusting any further maintenance and support for that addon to someone who may or may not be around in future. It should be common sense: you're making a trade-off between using a new feature that may be valuable to you, versus the uncertain level of support for that.
If a third-party developer disappears at any time - and it could happen to any other developer, for any reason at all - then I'm afraid they're the ones who have left you out in the cold. But you should have been aware that was a possibility, and if your project is important, perhaps made some preparations for it. After all often these are volunteers working on addons in their spare time - do you expect the same level of support as a for-profit company with full-time professional developers? No, that's unreasonable. They do what they can when they feel like it. That's the deal.
As I say it's happened before and will happen again. The problem is unreasonably expecting a professional level of support from third-party developers. If you are not aware of the deal you're making when you use a third-party addon, this is your wake-up call. Maybe you want to think a little bit more carefully about it next time you use a third-party addon.
If you're missing any really crucial features that you've previously depended on third-party addons for, you can post them or vote on them here: https://construct3.ideas.aha.io
Any really important ones we can build in as official features.